Personally I think the reason why Microsoft is behind HD DVD is mainly to confuse consumers and prolong the battle between Blu-Ray and HD DVD standards, knowing well that HD DVD is going to lose eventually. IMO this is at the cost of most consumers who rather prefer clarity. If the battle for the high definition format would have been more democratic there wouldn't have been a format war, it would be Blu-Ray and nothing else.
IMO one of the most severe cases of misinformation is that Microsoft pretends that they are giving people a choice between Blu-Ray and HD DVD. Yet they only offer HD DVD as an option, sure they can later release an external Blu-Ray drive (likewise an external HD DVD drive or maybe even a firmware update [backward compatibility, like some Blu-Ray players will allow] could allow the same with regard to the PS3), but the HD DVD drive they currently offer to consumers cannot even be used to benefit games...
