The nation's first 4G phone HTC EVO 4 (out this summer on Sprint) will be able to instantly become a mobile wifi hotspot (at 4G speeds) for upto (8) devices with the push of a button.
This done without buying an additional "mi-fi" device to elevate the speeds of your Wi-Fi only iPad.
Now...my 32GB wi-fi iPad will be become a 4G speed weapon at anytime, w/o depending on the At&T only network, originally planned by Apple.
Sprint - HTC EVO? 4G
Edit -- Also, be sure to check out http://www.htcevoforums.com/ if you are interested in the HTC EVO -- (admin)