I went the Android route for my phone and bought the latest offering from T-Mobile. The MyTouch 4G has a wonderful feature that allows me connect two wi-fi devices to it while still being able to use data on my phone.
Most Android 2.2 devices have a software based wireless router feature included unless your carrier nixed it. Works great with my wi-fi iPad and and anything else that I may need to get online on the road.
Best part so far is T-Mobile has not capped their data plans yet. 😀