The Guardian today reported that Representative Lamar Smith, the Texas Republican who authored the bill, had "conceded to calls for further investigation of claims that the legislation will damage the infrastructure of the internet." That concession was enough for Aaron Swartz, co-founder of Reddit, who called the decision "a huge victory for everyone who uses the Internet – and proof that millions of people speaking out can still make a difference in a Congress usually run by corporate lobbyists."
A quick recap: SOPA would allow private companies (especially movie and record companies, whose livelihoods depend on protecting intellectual property) to create a blacklist of websites that they deem to be infringing on copyrights. With a judge’s signature, the companies can then defund these sites by barring ad providers and banks from doing business with them. SOPA doesn’t affect sites ending in .com, .org, or .net, meaning that only non-US websites would be affected by the bill.
As it’s written now, SOPA would also force some pretty major technical changes to DNS, one of the technologies that underlies the Internet. The bill’s latest version would require Internet service providers like Comcast to bar customers from visiting a blacklisted site by blocking the site’s DNS or otherwise firewalling it. SOPA would also mandate the offending site’s removal from US search engine listings. Six amendments came up on Thursday that would have softened those provisions, but the Judiciary Committee voted each of them down. (One of these amendments would have exempted universities and research institutions from the blacklisting provision; the amendment’s failure means that these groups would also have to block their users from visiting infringing sites.)