WetMachine has a pretty good round-up of the day's events, being that one of their bloggers is a member of the Supreme Court Bar.
Funny exchange only to lawyers:
Scalia (sarcasticlly): But doesn't this come to us under summary judgment?
Lawyer: Yes, but under rule 56(b) we are entitled ...
Scalia: Surely you aren't accusing us of applying 12(b)(6)?
[laughter from Supreme Court Bar section, total confusion in regular audience section]
At issue here is whether the record companies can have their cake and eat it too: not only shut off the illegal file-sharing, but also shut down the entire P2P industry. It didn't seem that the Supremes were buying it:
Finally, the Court got down to cases, starting with Grokster. Don Virelli led off for the recording industry. He began with the assertion that Grokster's P2P software has no legitimate uses. The justices reacted skeptically. "Didn't the court below find lots of legitimate uses, such as distribution of public domain works or distribution of works authorized by the rights holders, even if the vast majority of traffic was arguably infringing?" Virelli stuck to his guns, thus falling prey to the trap that has undermined industry so many times in this fight: they over sell.
Scalia then started in on innovation: "But what about inventors? How will they know what people will use this for? Do they get a free ride for a few years to see if the predominant use is infringing or non-infringing?" Again, Virelli went too far. "In reality, these people don't get sued just for inventing stuff" he claimed, while the entire bar section rolled its eyes. Again, the Justices weren't buying. "Inventors need certainty they won't be sued or they won't invent," said Breyer.
Of course, the other side to that coin is whether the P2P people can just throw their hands into the air and say that what people do with their technology is not their business. This winking blind-eye approach is called "active inducement". Anyway, read the whole thing, as Green would say.