We're just going to keep this really simple for the small business owner who uses the Internet.
Start by reviewing this article from Mashable, with links to the full text of the bills and direct references in the analysis.
Another discussion in simpler terms and spelled out in the form of a hypothetical situation is available at the blog of Splendid Communications, a marketing firm catering to the wedding industry.
If you want it even simpler than that, here is an infographic. (Be patient. It's big.)
While much of the media focused on blocking foreign websites with bootlegged material or other malware (what I affectionately call "Chinese Takeout" due to the frequency of spam from that region) there are severe penalties for owners of US websites that are reported as "infringing".
Most people know next to nothing about copyright law. The public has become so used to seeing frequent images that they ASSume they are public domain. Very little is public domain. So if you even unknowingly have information on your website that crosses a copyright line, however obscure, however subjective, a complaint will cut your bottom line off at the knees. Online transactions and advertising can be blocked and you're relegated to the stone age. That's just inadvertent infringement. I'm not going to bother with deliberate theft that is passed on to an unknowing flunkie. It's covered in the Splendid Communications article.
A precaution I always take as a web designer is a boilerplate statement in all of my contracts that once the site goes live and ownership of the completed code is turned over to the customer, that the customer is legally liable for all of the content on the site. There are going to be webmasters thrown under the bus with a law like this: "Hey, it's not my fault. My web guy put it up. Prosecute them!" Not on my watch.
We're not just talking about commerce websites either, gang. All of you blog owners out there: John, Bob, Kerry, Rick, TOD, Paula, Cerebration, the other Bob, Donna, Lindsay, anybody else I missed - I know you're all reading this! - think about your comments section. (Except for TOD who doesn't allow comments.) You know how the spammers will sneak in their links by registering a Google ID, then posting some bland generic stuff on an old post and then a link to whatever it is they're hawking? And it takes you a while to find it and delete it? Under this bill, you're liable for that content. If no one notices, you get lucky, you delete the comment and go on your way. But if you miss it and someone complains, you're toast. I don't know about you but I never feel that lucky.
It's a couple of bad bills that need to go back into committee.
BTW - to get around the Wikipedia blackout: search your content and hover over the "stop" button on your browser. The nanosecond the content loads, hit the stop button. Read away. The graphics and presentation of Wikipedia's point were good but the JS implementation was amateur-hour.