Censorship and Freedom of Speech
Capatilist vs. Communist Theory on Speech and Press Freedoms
Freedom of information, speech and the press is firmly rooted in the structures of modern western democratic thought. With limited restrictions, every capitalist democracy has legal provisions protecting these rights. Even the UN Declaration of Human Rights, adopted by the general assembly in 1948 declares "Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers" (although as Article 19, it comes after the right to hold property, be married and hold a nationality, among others). As such, western ethics heavily favor the nearly unfettered rights to speech, press and information. Such rights might be tailored to protect state security from a Lockesian social contract perspective, but a Kantian categorical outlook surely provides for a society in which everyone can speak freely is better to one in which no one can speak freely.
Communism, as a primarily economic system, is much quieter on the issue of individual human rights. Two conflicting positions on these freedoms arise with analysis of communist theory. The first is an argument against individual freedoms. In a communist society, the individual's best interests are indistinguishable from the society's best interest. Thus, the idea of an individual freedom is incompatible with a communist ideology. The only reason to hold individual speech and information rights would be to better the society, a condition which would likely be met only in certain instances rather than across time, making the default a lack of freedom.
On the other hand, the idea of perfect equality in communism argues for a right of expression and press. Since each individual is equally important, each should have an equally valid point of view. Indeed, Marx defended the right to a freedom of the press, arguing in 1842 that restrictions, like censorship were instituted by the bourgeois elite. He claimed censorship is a tool of the powerful to oppress the powerless.
Indeed, many implementations of communism favored a constitutional democracy, albeit usually with only one party. Before and at the creation of many communist countries, a desire for freedom from the oppression of the proletariat by the bourgeois translated into strongly voiced support for individual freedoms for speech, dissent and information. Chairman Mao, in encouraging his countrymen to prepare for WWII more than a decade before he came to power, proclaimed "[the people] should subject ... the party in power, to severe criticism, and press and impel it to give up its one-party, one-class dictatorship and act according to the opinions of the people....The second matter concerns freedom of speech, assembly and association for the people. Without such freedom, it will be impossible to carry out the democratic reconstruction of the political system." In 1945, closer yet to his assumption of power, Mao proclaimed, "Two principles must be observed: (1) say all you know and say it without reserve; (2) Don't blame the speaker but take his words as a warning. Unless the principle of 'Don't blame the speaker" is observed genuinely and not falsely, the result will not be 'Say all you know and say it without reserve." More striking still is the fact that this latter quote is recorded in "Quotations from Chairman Mao Tse-Tung," more commonly known as the Little Red Book, a veritable bible of Chinese communism considered infallible during Mao's lifetime.
Thus, on the balance, it seems communist theory is compatible with freedoms of speech, information and protest, but it is far from a fundamental right such as it is under democracy and individual-centered ethics systems like that of Kant and Locke. Freedom of information should only be granted when communist society as a whole is likely to benefit. In this light, it makes much more sense that communist leaders, while still a persecuted opposition philosophy, would strongly support speech rights and later reject them when communism becomes the ruling system. At that point, access to oppositional speech and information is no longer beneficial to the communist state, and thus no longer needed in communist philosophy.
China in Practice
Modern day China, more than almost any other country in the world, severely restricts its citizens freedom of speech and expression. Oddly enough, Article 35 of the current Chinese constitution, written in 1982, stipulates "Citizens of the PRC have freedom of speech, publication, assembly, association, procession and demonstration." Up to the advent of the internet, the Chinese government had been able to successfully curtail this freedom in nearly all its physical manifestations. China has a tightly controlled traditional media, China forces all published information to be from official sources and to be vetted through the state. Ironically, the communist state founded on the 
backbone of Marx's words stipulates a minimum personal income of $35,000 dollars to be able to publish print media, an income level which could easily be considered bourgeois by Chinese standards. China also has strong restrictions against assembly and worship, demonstrated over the last few days with a crackdown on Tibetan protesters. Many assumed the government's ability to crack down on dissent would be destroyed by the increased prominence of a dynamic and nearly infinite internet space. However, China has adapted it's censorship policies to the internet, and by many standards managed to stay ahead of the curve in restricting free speech in the digital realm.
Internet use in China is blossoming. As of 2004 over 94 million users were online and in 2007 the China Internet Network Information Center, considered the premier source for measuring Chinese internet use, pegged the number of Chinese users at 210 million. This number will only grow in the foreseeable future, with the booming mobile market, more and more a popular portal to the internet, estimated to hit 600 million by 2010.
China Presents: The Internet (This realm has been modified from it's original version. It has been formatted to fit The Party's view of the world.)
This internet usage boom presents a variety of new challenges to a government adept at censoring traditional media types. The internet is much more vast than the physical realm controlled by China. It is not susceptible to the traditional local control structure relying on dedicated neighborhood party leaders to enforce edicts from the centralized government. Furthermore, the barriers to traditional information distribution of geography, money, and access to printing machinery, are no longer an issue in a digital realm where a cell phone or a few cents can buy time on the internet and allow anyone to blog their opinions.
China has responded with a vast centralized censorship program. One study by a group at Harvard in 2002, "found blocking of almost every kind of content. If it exists, China blocks at least some of it." The blocking has traditionally been centered on political and opinion based sites. Some of the most likely to be blocked are related to independence movements in Taiwan and Tibet, protest groups like the Falun-Gong, political parties opposed to the state, and sites on democracy. For the majority of Chinese web-users, these controversial topic-specific sites are not part of their daily internet routine, which focuses mostly on sports, entertainment and gaming sites. These users may have only the vaguest notion of the filtering being conducted by the government. Recently, however, the Great Firewall of China has evoked increased backblash as it has begun to block more popular websites like the photo-sharing site, Flickr and selected MySpace pages .
China's filtering and censorship program is regarded as the most sophisticated and effective in the world. It includes some 30,000 censors as well as technology, often provided by foreign companies like google and yahoo who are required to censor their results or be censored themselves. The filtering effort is in conjunction with a strict criminal prosecution system working with laws that forbid the publication of anything "(i) Denying the guiding status of Marxism, Mao Zedong Thought, or Deng Xiaoping Theory; (ii) Violating the Party line, guiding principles, or policies; (vii) Anything else that violates Party propaganda discipline or violates national publishing administration regulations." These laws are enforced with the aid of laws requiring all ISPs and internet cafes to record and store information about all users and their internet use.
Conclusions
It appears that the modern Chinese government has no interest in conforming to the platitudes of free speech, press and dissent espoused by Marx, Mao and it's own active constitution. While dissent may seem compatible within the framework of theoretical communism, it appears to be at odds with the communism practiced in China. In revoking its founders statements, the government's position may seem to oppose the spirit of communism; yet, the choices make perfect sense when considered in the framework of making decisions not on a priori ethical assumptions like democracies aspire to do, but rather on the basis of what is best for the communist society at the moment. While the world wide web may yet be too much for the well-oiled Chinese censorship machine to handle, the government has done remarkably well so far in providing a slimmer, more China-friendly version of the internet to its citizens.