Since its so little more, and I would prefer the 850MHz of the XT phone, I am seriously considering getting it rather than the 845.
How are they as a phone? the 845 seems good, but has that one problem that I will never be able to use it on XT, which getting the sammy solves, but I was quite happy with the touchscreen on the 845 whereas the samsung has a capacitive one, and IME they vary from terrible to tolerable.
Both are old android 2.1, crap cameras, but basically I just want browsing and twitter/facebook aps, so the total inability to run angry birds acceptably is not a problem.