Phase is the same (both are single phase), but frequency is different (60Hz in the US, 50Hz in Europe) as well as the different voltage. There are units specifically built to allow 120V/60Hz units to operate on 220V/50Hz. That being said, Peter's offer (lining up some sort of swap for a unit with a power supply that can operate on 220V/50Hz) is even simpler - especially with the different tuner.

Europe does use PAL instead of NTSC for its standard definition video format (and the difference between 50Hz and 60Hz means that you have to be careful with PAL/NTSC conversion to avoid speeding up or slowing down the signal). Neither PAL nor NTSC apply with HD source material, but it will still matter for DVD's and other SD video sources.