Pilot program is live look for ads showing up on sites. Google might have to ad a couple of new features to Adsense
Reports seem to be delayed. You can make blends in the background, add gradient, or image backgrounds. Also can change font, drop shadow, solid or dotted outline. No more than two ad blocks per page, ads somewhat targeted.
Ads are served to more than just U.S. visitors, but they are only allowing US publishers due to IRS reasons.
Sounds interesting - I applied a while ago on their "sign-up" page ... but haven't heard anything ... be nice to take Publisher for a spin and see how well it works (in case anyone from Microsoft is reading this - hint, hint! ;-)