Ever since I heard about the MySpace HyperTargeting program last December, I've been looking for information about how it's been performing.
The theory, which we're proving to Others Online partners and which HyperTargeting is testing, is that ads in social network situations are better targeted not by the context of the page you're on, but on the content you write within your own profile/pages.
Looks like they're reporting 300% increase in clicks in initial tests.
UPDATE: Found a little more information on how MySpace HyperTargeting works and how they're charging. Looks like they are segmenting users into proprietary categories based on the information in their profiles, then selling those categories on a CPM basis at a 50% premium.