I don't need a data plan but maybe i'll want one in the future or when i travel. I have verizon as a cell phone (not smartphone) carrier so they'd be the natural choicel Will data plans always be GSM or CDMA tech and be compatible with the ipad 2? I just heard ATT's has a sim card slot and verizon's doesn't so it makes me think ATT's is more "flexible" in terms of carriers? does this make sense?