Every time a terrible bill like COICA or PIPA gets exposed for what it would actually do to the Internet, large rights holders reinvent it slightly, lay some bad dubstep over it, and call it something you can dance to.
This time it's the Stopping Online Piracy Act—SOPA for short. SOPA is a bill coming out of the House that is a compliment to the Senate's PROTECT-IP abomination. It's entirely unlike PROTECT-IP, in that while it does all the same things and worse, it phrases them differently… so you won't notice.
SOPA has done away with PROTECT-IP's "blacklist," after realizing Americans don't really like blacklist censorship. Instead, SOPA allows the attorney general to cut off sites from the Internet by prohibiting them in some sort of non-list document. Since that's not a blacklist, it doesn't need any judicial review. Prohibited sites would be arranged in a tag cloud of some sort, and DNS providers would be required to not show them to you.
SOPA goes on to ban advertisers and credit card processors from doing business with sites dedicated to copyright infringement. Whether a site is dedicated to infringement is helpfully determined by what the guy filing the legal nastygram thinks looks like a site dedicated to infringement, without any law enforcement getting into the act, much less judges.
The law calls this the "market-based approach." This provision could not possibly be abused as much as the infamous DMCA take-down notice, a provision used more to hobble competition and speech than protect copyright, according to a Google study, because I heard recently that all the bad people left the Internet.
This bill may let corporations and government break the Internet, but don't worry, because they've put out press releases promising they would never do anything like that.