1) Do you want a physical keyboard?
2) Does size matter?
Let's take a look at number one. Do you want a physical keyboard? If the answer is yes then I recommend looking at one of three phones.
Out of these three Android phones I personally would go with the Droid or Droid 2. It would be a matter of which keyboard feels the best. The new Droid 2 has a slippery feel unlike the Droid.
If a physical keyboard does not matter then I would ask you Does size matter? I've had both the Motorola DROID X Android Phone (current device) and HTC Incredible Android Phone and love them both. It came down to wanting a larger screen however, my wife loves the size and feel of the HTC Incredible.
Do your own homework to help you decide. Take a look at this excellent Droid X Review and don't forget the review of the HTC Incredible. Might want to compare the Droid X vs the HTC Incredible. A well thought out review of the Droid 2 is located here. For those wanting to compare the Droid 2 vs the Droid this is a must read. I know it can be overwhelming but all else fails walking into a local Verizon store and touch all of them. Do not hesitate to spend a few minutes at each one playing and calling people. Well worth the time when you are dealing with a 2 year contract or extension.
No matter what way you decide to go at least your going with an Android device.