Adobe has updated Bridge CS3 to address a variety of issues. To install the Beta 2 you must have the original Photoshop CS3 beta installed. You will need to use your Adobe ID to log on in order to download the update. The Mac version is 157MBs while the Windows version is 72MBs.
The download and additional info is available on the Photoshop CS3 product page.
To read more about the Bridge Beta 2 release, check out this post on the Bridge CS3 forum.