I would guess that some IT flight would occur, but mostly, SOPA will be (and it will pass) a bonus for lawyers. Nothing will happen for a while, some really egregiouis sites will get Great Firewalled. Then someone with really deep pockets and user-generated content will get sued. There will be a frenzy of removing blogs, sites with user-generated contents, etc etc. After a while, a few big sites will get enough lawyers on-board to censor user-generated content, and we'll be back in the situation of the 1970s, where a few large newspapers could have lively "letters to the editors" pages, but nobody else could afford it.

Welcome to TV 2.0!