Wrong section but iPhone every time.
You will get the anti-anything-popular brigade telling you not to get one because everyones got one, but theres a reason its so popular and its not because everyone follows others.
Its not perfect by any means, but as far as phones go its the most user friendly phone you'll ever have, its the app store that makes it what it is, and thats something that no other phone will ever have in the same way that apple have, they've got market dominance there now.
However, i'd wait till June 22nd when they announce the new iphone (rumored to be the iphone HD) before you make any decision, if you get a 3GS now you'll be gutted when the new one comeso ut.