need to switch iPhones with my wife

My wife and I both have 3g iPhones. The gps chip in my phone must have gone bad, because the phone can now only provide approximate location data, presumably through cell tower location. My wife never uses any programs that take advantage of the gps, so I want to switch phones with her, so I can use all my location-aware apps like Runkeeper and so forth. My understanding is that switching out the SIM cards with switch our phone numbers, but I need to know how to switch all the other settings (contacts, calendars, media, apps).
My wife's phone syncs with iTunes on a Macbook, mine syncs with iTunes on XP. Our music library is on a SMB share on a separate machine, and we each carry different subsets of that music around on our phones. Both phones are set up to sync e-mail, contacts, and calendars OTA with Google. Also, it would be nice to preserve recent call logs and SMS logs.
So can anyone tell me, step-by-step, how to pull off a two-way iPhone clone? Thanks everyone.

If you swap the SIM's your numbers will move along with you to the new phones. When you do plug in the iPhone to iTunes with the switched SIM's, I'm thinking that iTunes is going to say it's a new phone and try to re-sync.

As far as the settings go, those are stored on the phone and not exported, so I'm guessing that you can't transfer that, and same goes for the recent call logs and SMS logs..

Perhaps a quick call to your carrier might shed some light, but I'm guessing that you'll need to talk to Apple to get these iPhone specific answers..

Regards

The iPhone does not store contact info or any settings etc on the sim. I just swapped sims with a replacement iPhone 10 days ago so trust me.

Hope this helps