It looks like the MPAA is about to drop the hammer on Bittorrent and eDonkey by cutting users off at the pass.
According to an Associated Press report, the MPAA will begin filing suit against server operators - the folks that bring you Bittorrent "trackers" and eDonkey services.
This does not bode well for sites such as Suprnova, regardless of legality. Napster managed to essentially escape the wrath of the RIAA legally, but was crushed by the legal bills that accompanied their defense. There's nothing to indicate that this situation will be any different.
There's no real difference between the Napster case and any number of others here, as those technologies were also just providing "links" to the files. Still, you can expect sites like Suprnova to move operations to locations that won't prosecute them - or you can expect sites like Suprnova to disappear completely.