It was a long day but time went by quickly. My phone is working good. The 1.5 stock build was good, but the 2.1 with the O2 build is better.
I really only have one issue and that is that Dell removed the Right & Left Arrows Keys when they took the number pad off the stock Keyboard. If I had a track ball I would not care, but now how do we arrow around to edit?
A nice change if you use the stock email client is they added check boxes and stars to the inbox.
The desktop UI is a little different, but there are apps for that. The USB cable connected message and controls are now up in the message bar. The screen lock is different. Because they removed the number pad the keyboard is bigger. I'm sure there is lots of other good stuff I have not found yet.
The whole update process would have gone faster if I had had better instructions before I started. I hope you will find my notes helpful. I did not include where to find files on the internet because those things change.
My first mistake was my phone was powered off when I plugged it into my PC so my PC did not see it, and since I did not realize this I installed and uninstalled the Dell PC Suite way to many times.
Second mistake I did not realize I needed to install another driver in the middle of the upgrade, so I wasted a lot of time trying to figure out why it would not connect.
Third mistake driver issues again while trying to get PdaNet working. The problem this time is I had already installed PdaNet before for my HTC Aria. I had to uninstall PdaNet and reinstall it to load the correct drivers for the Dell Streak.
Many of the directions I found on the web include extra steps that were not needed. You do not need to Root the phone, and no third party apps are needed to upgrade the phones OS. The only 3rd party app I used was PdaNet and that was for the tethering.
In the end even the Dell PC suite is no longer needed. The last time I uninstalled it I left it uninstalled because the USB drive and USB tethering both worked and I had no other use for the Dell PC Suite at that point. My contacts, email, and calendar are all synced by Google.