Battery life isnt great... at all.
Lots of good apps (Not as many as the iPhone perhaps... But they are good non-the-less). Google have made a few (The My Tracks app is great if you like cycling/walking..). GeoBeagle is good if your into Geocaching.
There are some decent games... However, not many 3D ones (You must remember that as the Android Platform develops, more phones will be released.. which will result in more apps.
The Keyboard hardware keyboard is really good, as is the trackball thing.
Quite a few apps make use of the in-built compass.
It's cool how you can get widgets for the home screen. I currently have a FML and Weather Widget on there, along with a google search bar and a clock :P
I will have a search for some emulators now...
I wouldnt get the Omnia. I really dislike the interface - it feels kinda cheap