I am chugging a blackjack now, it's a clunky, but it works. if it's cheap, get it. (If you're on at&t). Seven Beta works so you can get your email pushed, there are good apps for twitter and IM clients that work well. 3G is fast as any other device. The browsing sucks, but it's not the worst. My biggest gripe after having a BB for three weeks is no copy & Paste, and occasionally some embarrassing T9 miscorrections. The newest OS for it is winmo 6.0, which you can get from samsung's website. Overall it's very functional, but again, I have to honestly say I am sick of it and deciding whether I am about to replace it with a TP2 or a 9700, Or that Tao/Sholes. That thing has my eye.
But it can hold you over if you're waiting on the right decision and don't have to sign a contract for it.
Posted from my CrackBerry at wapforums.crackberry.com