Android = a more technically inclined person who wants to infinitely customize, tweak, and really get the absolute most out of a device. Unfortunately the device was oversold to way too many unassuming consumers who don't have that mentality but still wanted a smartphone. There is/will be a backlash.
iPhone = loves to play with the device, wants the features, Okay with having it served up Steve's way, and having it locked down. Apart from a few shortcomings, the hardware is beautifully engineered. Unfortunately it has the reputation for being the perfect device for 21 year old girls, isn't very corporate friendly, and is available from one vendor with virtually no options.
Blackberry = the old school hard-core communicators. They'll eventually migrate to other platforms but for now they're still mostly die hard fans, addicted to digital communication. Blackberry still has the nicest threading and blending of diverse messages of any platform. Several have tried to copy it, but have fallen short. Unfortunately it's a slowly dying platform that's being out-featured by nearly everything else.
Windows phone = somebody who already has enough complexity in their lives, and just wants a device to easily server them the information they need. It's a phone, not a friend, a toy, or an entertainment platform. Bells and whistles are nice, but give them the basics and let them get on with their lives. Unfortunately the platform will forever be considered late to the party and under featured, even though many of the features found in other devices are used for a week or two and then forgotten.
http://www.engadget.com/2011/11/03/n...ia-800-review/