The Dell Streak is a pretty cool device, at least in theory. It is basically a 5 inch capacitive screen smartphone. Dell is marketing it as a 5 inch tablet with voice capabilities. It has some pretty good specs, but it is plagued by Dell's custom user experience running Android 1.6. There were a number of complaints including the lack of multi-touch and a pretty awful keyboard.
Engadget just received an update to 2.1 for their review unit. It makes the device a ton better. To begin with, there is a keyboard update that gets rid of the numpad and caps lock. This makes the typing experience much better as it is now more balanced. There is not multi-touch in the keyboard, but it is definitely a lot better.
Google Maps now has pinch zooming. The dialer also got an update; it is now better looking and more functional, including the favorites and contacts within the same app.
It also comes with the default Gallery app, allowing linking up with Picasa. That said, now it is lacking the cool features that the Dell UI Gallery originally added. You can't have your cake and eat it too.
On the original firmware, you were supposed to be able to skip a song by double pressing the button on the handsfree headset. Unfortunately, this only worked if the screen was on. Dell fixed this bug.
The camera app got a pretty big revamp, with pretty much the same features but just moved around a bit. The camcorder now can shoot in 720p.
You still have to hold the phone in landscape mode on the homescreens. You can of course install an alternate homescreen to remedy that. They also made changes to how many icons can fit on a screen (it's less...), as well as the width of the Dell widgets. You can no longer have two of their widgets next to each other as they are just a little to wide. The homescreen switcher button in the top status bar has been switched for a recent applications button.
These are of course on top of all the improvements that 2.1 brings over 1.6, including speed and efficiency as well as live wallpapers.
These updates will be appearing O2 shortly, with Froyo lagging somewhere behind. It is unclear at this moment who else may or may not be getting this update, or when.
Here is a video demonstrating the new UI: