Smartphones/Crackberrys
I have T-Mobile and I'm currently using the Blackberry 7105t model, but I'm about to upgrade to the white Blackberry Pearl. I do like the Blackberry phones, except I find them way too bulky which is why I had the 7105 model and I'm now looking at the Pearl. You get the same features just in a smaller/sleeker package.
I've been with Cingular, AT&T(before the merge), and now T-Mobile. I really don't like Cingular because I feel it's too expensive for what you get and the customer service was horrible when I was a customer. Plus, I always had billing issues with them.
Right now, I have 1500 minutes with T-Mobile for $49.99 a month. My contract is up and I'm probably going to stay with this plan for as long as possible.
I've seen advertisements for an almost free Blackberry phone with a new signup with T-Mobile. You may want to check into that....