Swapping Phones w/Wife (She has 4.0.1, I have 4.0.2)

[AggiePhil]

OK, so I just got a brand new iPhone 4 and of course it shipped with 4.0.2. Only saving grace is that my wife's had her iPhone 4 for a couple months now and hers still has 4.0.1 on it. Question is, what is the best way to swap phones with her so that she doesn't lose any of her data and we can transfer over the activations and everything? Should I just activate the new iPhone 4 as though it's going to be mine and then swap its SIM card with her phone or what? I'm also not sure if or how that'll mess with the phone's "Apple registration".

FWIW, I'm upgrading from a jailbroken iPhone 3G running 3.1.3.

Got em switched successfully.