I like the idea of having an all in 1 device so to speak. Throw in Sprint navi as a bonus too. I use my phone as my mp3 player so the upgradeable memory was a must after coming from a Motorola Q.
Data plans are cheap. If I want FM radio I can just stream it to my phone. So, what can't this phone do really? You get so much hackability (is that even a word?) with winmo.
I like being able to customize and tweak till my hearts content. Lots of "free" alternative software out there. Opera browser is pretty sweet.
Battery leaves a lot to be desired but it's not a deal breaker. Just learned to deal with it.
Not to mention it's wrapped in sexy hardware even though it is a little on the thick side. Nothin wrong with havin' some meat on them bones.
Oh, and I can use it to make calls too