I have an HD2.
As said should do most of what you want.
Great screen – wanted for Anquet mapping – although the GPS locator doesn't work with it….yet. Google maps is great tho.
Twitter doesn't work with mine.
Most things are ok, but there are a few annoying operating problems sometimes. However Windows 7 may be available as an upgrade on it sometime (I hope).
Very happy, but then I also don't worry about having lots of apps.