I'm gonna give it to you straight mate. No sugar coating.

If you are not a coder, do not have time to actually learn a great deal or do not have the patience of a camel. Don't get the n900.

If you just want a Nokia. Wait for the N8 or something more polished.

If a jailbreak is released quickly, then get an iPhone 4G hands down.

Otherwise, get an HTC Legend or Desire or Milestone if you want a keyboard.

HTC HD2 is not bad, windows is legacy. but it runs.