my 2 cents are these:
first penny:
If you live in a sprint 4g zone buy an evo (it kicks ***)
second penny:
if not get a nexus one it appears to have amazing community and Google support... Nokia support is lacking at the best.

dont buy the n900
unless you want to develop on it

it has fairly bad battery life
poor support
average camera

If i could go back and repurchase a phone (I got it maybe 3 months ago)
I would have gone with the nexus one
however I have come to deal with the n900s faults and I don't regret it even if I am envious of the nexus' new camera support