Hm, can't say I've heard of tires squeaking on pavement before. My first guess would have been the little dust seals on your front hub. Those sometimes get stuck to the axle and will spin against the hub and squeak a little. But it's most likely your disk brake--and some light rubbing/squeaking is inherent of all disk brakes.
You could also try giving it some true metal from the king of kings. That might work too.
Manowar is so awesome.