Google Nexus S phone.....



Got one, love the display. Battery life is pretty good for a smartphone too, it holds at least 2 days on average usage.

It's pretty fast too (altho no dual core, but android's not optimized for that anyway) and being a "pure" android (no manufacturer skins like samsungs other phones or htc's sense) makes sure you'll get great support from the mod community for a long long time
 
I had a Nexus S with Sprint and I hated it. Feels cheap, slow, and the touchscreen has the worst sensitivity of any phone I've used in a long time. Battery was decent. There's no cool car accessories like there was for the Nexus One (I loved that car dock). I eventually went with the HTC Inspire. I like Android better than iOS but the iPhone hardware is definitely a notch above.
 
The nexus S is made by Samsung. If possible, go with the Samsung Galaxy s2.. Compared to nexus, it has better display faster processor (dual core), slimmer design and expandable memory (SD card slot).. Nexus S lacks sd card slot.

The sd card slot is just a personal preference. For me its a must as you just can store all your data in the card (apps, music, photos, numbers everything).. so even if your phone dies or you just want to use another phone (while roaming etc etc), you can just drop the sd card into another android phone and it works very well.