Here are some good links to see the 2009 Super Bowl ads:

My pick for best place to watch the ads. The interface is easy to navigate and the ads are broken up by quarters making it easy to find a specific ad. Video quality is good and it offers fullscreen capability.

Best quality videos w/fullscreen, but usability isn't the greatest if you want to quickly go through all the ads without accidentally clicking on an unrelated one.
http://www.spike.com/superbowl

This is the official Super Bowl site has some commercials I didn't find on the other sites, although you have to endure an NFL commercial before previewing the commercials...oh and there is no fullscreen capability
http://www.nfl.com/superbowl/43/videos/commercials