When I ordered mine they added HSDPA to it as an option but I think I just got really lucky - I missed out on getting the free bump to HSDPA last time so I guess its my turn! Or maybe i'm paying £5 a month for it, not totally sure to be honest :D
Only tried it at home so far where I quite often get no signal and its alternating between a "G" and an "H" (thats next to the kitchen window!) - speed test shows about 380k - had to up the file size because the mobile ones completed too quickly to measure but I doubt its really going HSDPA due to the signal here.
I will try at work tomorrow, should be able to get a good signal and speed there.