I love this topic. Smartphones and I go a ways back. I started out with the Nokia 3650,
which was a lot of fun. You could do all kinds of cool stuff with it, but you pretty much had to "brew your own."
When EDGE networks (providing faster data connections) became available, I got a Nokia 6620 (which was the North American version of the 6600, I think).
Finally, Nokia came out with the N95, shortly before Apple released the first iPhone. On paper the N95 was superior to the first iPhone in every way. It had a better camera, 3G data capability, user-replaceable battery, and a memory card expansion slot. I bought one.
That proved to be an expensive mistake. Compared to the iPhone, this thing was sluggish, had a clunky interface, and no ecosystem to speak of. "Brewing your own" was fun in 2003. By 2008-9, not so much. I ditched it about a year after I bought it.
By then, the iPhone 3Gs was out and I got that. It's the phone I use right now (holding out for iPhone 5).
The advantages for the iPhone over Android are:
Better hardware/software integration; Android tends to be a little sluggish (just check the more comprehensive reviews).
No spyware; Apple exercises tight control over what gets on its devices. On Android you've got to worry about everything from apps that take far more of your details than they need (without your knowledge or permission), to Carrier IQ, which is present on most Android devices and can send your keystrokes and even screenshots to the operator. I'd just as soon not worry about that.
The slick, smooth interface and the tight software/hardware integration are reasons enough to go with the iPhone. It really does "just work" and it's amazing.