A lot of people love the Blackberry. Some people I know like them over android phones but I personally like android a lot more so I guess that boils down to personal opinion, so I'd suggest trying both out.
I've never used a Windows phone nor do I know of anyone who owns one...
I would recommend an Android over a Blackberry just because you can do more with them. Blackberries are pretty much strictly business; their app store is very limited and the hardware not the greatest.
As far as WP goes, WP6 and before was horrid. I haven't used WP7 yet, but it's gotten very good reviews. I'd check it out before making a decision.
Also I'd go with the iPhone myself. In my opinion it has the better OS and I just dislike smartphones that aren't iPhones or Windows Phones, but since Windows Phones aren't part of the discussion I say iPhone.
--------------------------------------------------------------------------- Trust is a fragile thing. Once trust is lost, it can be impossible to recover. Those we're closest to can betray us,and total strangers can come to our rescue. In the end, most people decide to trust only themselves. It really is the simplest way to keep from getting burned.
I've had an Android (original model) since last Christmas Eve, and I love it.
--------------------------------------------------------------------------- a.k.a. Ryan ~~CHU Thread Of The Year 2007 & 2008 Winner~~ --------------------------------------------------- CHUUL - Cheathappens Unlimited User League - Currently Inactive http://www.cheathappens.com/show_board.asp?titleID=642