I think this lawsuit is just about people who watch ENTIRE videos and whatnot. There is a rule regarding sampling, which I'm assuming would be the same here. I highly doubt Viacom is going to care if someone posts a 40 second clip of a show that they found funny. It's the people posting whole episodes that gets their goat.

However, technically this ISN'T a breach as far as I have been informed regarding copyright laws. It would be illegal if the programs were available on DVD. Like Daily Show and Colbert, they aren't available on DVD, so fans stream it. Sure you can catch it on re-runs, but the issue is, how are we supposed to see what we miss? That is as far as my understanding goes, but it might be a bit dated. Been two years since I spoke with a lawyer regarding that issue.

So yeah, you can share, but not the entire freakin' episode haha.