well you can eliminate the omnia 2 right now. it really is a descision between droid and droid eris.
personally i would go for the droid eris for the folowing reasons:
the special HTC user interface HTC Sense is incuded in the eris, and the UI is very easy to use and has more features than the Moto Droid UI.
The HTC droid eris has a trackball, making navigating on the internet much easier and allowin you to do a lot more with your phone.
The HTC droid eris is also thinner and smaller. It is true that the Moto droid has a keyboard, but it is very cramped and uncomfortable so you will end up using the touch keyboard anyway.
The HTC droid Eris has a special virtual keyboard made by HTC that is a lot better than the standard android or Moto Droid keyboard.
HTC droid eris has integrated facebook and twitter.
HTC droid eris also has a proximity sensor(google that if u dont know what it is)
HTC droid eris has a flash player so you can watch almost all videos on the internet.
HTC Droid eris also is much cheaper and is better build quality.
well there you go
but if i were you i would wait a month or 2 until the Nexus One comes to verizon.