a great piece by jason snell comparing and contrasting both phones - from ui elements, to its hardware.

while the piece is rather long, here is what i took away as a quick summary:

"if you’re a tech-savvy person who enjoys tweaking your system, installing add-on utilities, swapping in new hard drives, and that sort of thing, android will fit the bill better than the iphone. but the reason apple sands off all those edges and reduces user options is not out of some insane degree of control-freakishness: apple sands off the edges and reduces user options because most people don’t want edges and options on their tech products.

even many tech-savvy people—and i'm including myself in this category—would prefer to have a phone that just works, rather than a phone they can hack within an inch of its life. that’s the path apple has chosen to walk with the iphone, and so far the company has seen massive benefit from that philosophy.

i would not hesitate to recommend a nexus one to a computer-geek friend of mine, especially one who has grown tired of apple’s app store policies. but I’d warn them first that they’ll be trading a lot of well thought-out user experience, of usability."

however, this stuck out to me:

"if the iphone didn’t exist, i would have the nexus one in my pocket right now—but then again, if the iphone didn’t exist, the nexus one wouldn’t either."