Well the internet is still the wild west of the technology age but yes indeed efforts to control it have succeeded. Napster is a hollow shell compaired to what it was so no, not to no avail. The US government is obviously nipping around the edges on this powerful medium of free speech. When they feel that they can get away with biting a big chunk, they sure as hell will.
As soon as Napster folded, ten and more popped up to take its place. As evidence I cite the total ineffectiveness of the RIAA with all its resource to slow down file sharing (information distribution) one whit.
And to be sure, I agree Central Government will attempt censorship, but it will fail, I opine. See 'Gutenberg,' 'Bible,' and 'Roman Catholic Church.'