Here's the LawMeme discussion along with a nice synopsis by Lisa M. Bowman for CNET:
File-traders in the crosshairs.

From CNET article:

Jennison thinks the RIAA will target people in their late 20s or early 30s who are making available massive numbers of files that are current and popular. The RIAA may also look for people who could otherwise afford to buy CDs but instead choose to play the free-swapping game, she speculated.

Others suggest that the industry would pursue, as University of Wisconsin's Vaidhyanathan called them, "hacker types," or people who look like they might spell trouble to mainstream Americans. Already, similar tactics have been put in play by the movie industry, which successfully convinced several judges that the operators of hacker publication 2600 aided copyright infringement by providing links to code that could be used to crack copyright protections on DVDs.

The record industry also could lean on law enforcement to do its dirty work for it, said P.J. McNealy, a research director at Gartner. "One of the problems with file-sharing right now is consumers aren't afraid of police knocking in doors and seizing computers," he said. However, criminal copyright charges, which usually must involve monetary losses or an intent to make money, often are hard to prove in cases involving individuals.