lets not confuse HDDVD with BlueRay.
The two formats are incompatible, with HDDVD being supported on the Xbox360 via a �99 add on drive and BlueRay being supported by the Playstation3 straight out of the box.
HDDVD is being backed by some movie studios and BlueRay by the others. This means that most films are being released on one format or the other but not both. So at the moment to watch all the films in HD you need both systems
I myself have and Xbox360 which at the moment has the majority of the games but the PS3 should start to catch up in the next 12-18 months