My contract with t-mobile on my kaiser is up. I don't know whether to upgrade now or not. Problem is, I like the touch pro 2 and the xperia 2 is coming out next month(not bothered about changing network if I have to as am more concerned about phone and internet on phone than network). Both look great phones. They both use windows mobile 6.5(which I've been using on my kaiser for ages), but there are now more rumours about windows mobile 7 coming out next year and kicking major a**.
Android phones are getting better and better(I think it'll be a year though before it is really good), so I'm not decided on those phones yet either.
I'm wary about commiting myself to an 18/24 month contract with a lot of possible changes coming out in the next year. I know you can say that something better is always round the corner, but I've found that nothing has really come close to my kaiser in the past 18 months, and I want as future proof a phone as possible.