Activesync is awesome when it works like it is supposed to: Plug in the device, let it sync. Unplug.
But then, you start getting the typical "Microsoft errors" that help nobody, including the end user fix them. It has nothing to do with my previous time at T-Mobile (I was actually an Activesync SME, and people from all over the center came to me for help with it), Activesync is crap, and it doesn't work very well. Its like trying to use the Blackberry Redirector. That is also crap software. The difference is that Blackberry has an awesome built in mail client that works wonders (Windows Mobile does too, through a built in ActiveSync application that works pretty well, until it fails and you have to try to fix it through Activesync on the PC, which is also failing).
A phone should be a phone, working standalone from a PC. For the reason for that, try reloading Blackberry operating system software with a Macintosh. Unless you buy an expensive software package, it won't happen. Windows Mobile and the Android give you the ability to do it without using a computer.
But that's deep techy stuff. From the consumer's POV:
1) Free apps
2) Phone choices
3) Carrier choices
That is what matters. Blackberry, Windows Mobile and Android have all of the above. the iPhone has 1 of the above, and their free apps suck, for the most part.