On a 7,2mpbs note, operators here in Sweden had to back pedal on getting 7,2mbps. It seems around 1mbps is needed for package loss/correction (perhaps someone who knows this stuff wants to chime in?).
The ads now say "up to 6mbps" which I do reach (also depends on traffic congestion) when tethering my 3GS, which has been my only internet connection for the last 18 months (no cap what so ever).
I sometimes ponder, wearing my tinfoil hat, if it's the US networks that are holding the hardware down (or rather the fact that one has to pay through the nose for any meaningful data package over there).
There are 16mbps mobile broadband packages with unlimited data (no hard/soft cap) for $40/month, which is the price of most wired home connections over here.
I'd love for Apple to beef up the connection speed in their iDevices.
It's also a bit ironic to tether my 3GS to download apps over 20 mb just to transfer it back (iPhone -> MBP -> iPhone).