Dell has quietly released a new version of its official Android 2.2 ROM for unlocked Streaks.
There's no documentation accompanying build 12821, but those who have applied the update report that the web browser redirect issue from older builds has been resolved. That seems to be the biggest and most commonly noticed fix, though some people who previously had issues with 720p recording and Android Market crashes say those have been fixed as well.
There are two download links going around that I've seen:
Both lead to the download of the Streak_318_12821_00 package, which can be accessed here:
The file is 150MB like one of the earlier packages. Updating will change your baseband to GAUSB1A131800.
As for which versions of the Streak are able to install the update, there's a good amount of information to wade through on all the Streak forums (see links below), so I suggest you start there to see if your version is mentioned. I've heard success stories from people whose original builds were 11548 and 12332, which are the official Dell ROMs, so you should be fine if you're on any of those.[Pocketables Forum | MoDaCo | xda-developers 1 & 2]
Thanks to everyone who sent this in!