Via Email from the ad team:
The most basic change that you’ll notice is that ads will now appear on the right side of Facebook pages instead of on the left. The new placement integrates the ads into the new site design in a meaningful way. As many as two ads may show at one time on any given page.
In addition to these changes, you will also see a new ad on the home page. This new ad is located just to the right of the News Feed, and will initially run a limited set of advertisers. As this space continues to evolve and improve, we’ll provide more details.
So at least three ads on a profile now? (Not including banners) General users can’t bid on the one next to the newsfeed. We’ll see more tomorrow I suppose when the new look goes live.