I'll be traveling to Japan later this month and wondering if I'll be able to set up 3G usage over there. I typically use international data roaming on my iPhone and get 3G just fine over there (except it's a little pricy), but would much rather use the iPad now that I have it. Or could I just go to DoCoMo or SoftBank and get a sim card for some kind of prepaid plan? Anyone done this yet? Thanks for any advice!