I am using an HTC Desire mobile for the last few months. For better integration I created a Google account. I am using Google Mail, Calendar, Tasks, Docs. The integration works really well without the need for any desktop application. I can access the data whereever I can access the web. After 7 years of using Windows Mobile I am really happy with my decision to change to Android.
The Over-The-Air update to Android 2.2. (Froyo) also worked without any problem and brought more stability to the system. Concerning the performance, I did not notice any difference.
Here is a list of imho best Android APPs:
Tools
Games
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