BlackBerry Storm owners, an "official" beta (yep, that's an actual phrase) of OS 188.8.131.52 is out, and if you're craving threaded text messaging, a 3G icon (instead of that boring old "1XEV" garbage), and enhanced icons, it's the beta build for you. Reaction to the build seems positive; the camera works well, and many have been successful in getting Facebook 1.6 to load (previously Facebook 1.6 didn't work with any OS 5.0 build). If you want to read a bit more about it prior to downloading, a 3 page (and growing) thread can be found in the Crackberry forums.
OS 184.108.40.206 can be downloaded here.
Editor's Note: Downloading any unofficial software build is always risky, especially if you're not familiar with the process. Any downloading and installing is done at your own risk!