Definitely wanted a Nexus one, but decided to go with a new Iphone. I like you get the updates right away and don’t have to screw around.
How’s the battery life? Heard mixed things
How’s the battery life? Heard mixed things
Few things there. First, while I really, really like my Nexus for a lot of reasons, I don't know that I would recommend it to someone in that cost a lot of loot. $529 for the unlocked version that I needed to run on AT&T. And now that Google stopped selling it online (due to the failure of the buy-before-touching model) the only way to get it (currently, may change) is pay $25 or so to register as an Android developer, which makes it even more expensive. For that amount of money (or less if you're willing to enter a contract) you can get another Android phone that has even more features.
OTOH, the Nexus One has a great form factor for its feature set, more pocketable than any other comperable phone that I know of. And as you said it gets the new updates right away (probably only a guarantee for the next version, 3.0) and it has good battery life for its competition. So the buyer needs to consider what his priorities are.
Speaking of your second question, I get about a full sunrise to sunset day of use from my Nexus before it starts getting really empty. That's with moderate data (including wi-fi) and screen use, and light phone use. Pandora radio to and from work can not be discounted as a factor here. I've gotten used to plugging it into my car charger and work computer to keep it topped off, just because, but short answer, you'll get about a day, no more. I understand that the Evo is not as good, probably due to more hardware to run (keyboard) and its bigger screen.
For most Android phones, including the Nexus and Evo, you can buy a higher capacity battery that can be swapped out for the standard one. They run around $40-$45.