The only reason that The Matrix trilogy hasn't already been released is that, at the time of release, the Blu-ray players that were available couldn't support all of the features that were on the HD DVD version of the discs.
I don't remember if HD DVD version utilized the Internet for any special features or not. If it didn't, it's likely that a Blu-ray version will be available sometime this year. If it does utilize the Internet, then we probably won't see The Matrix on Blu-ray for another year or two, when Blu-ray players catch up with the first generation of HD DVD players as far as technical capabilities are concerned.
Movies released by Warner are a no-brainer's as far as being released on Blu-ray. The bigger question will be movies that are released by Paramount & Dreamworks. These two studios supposedly have an exclusive contract with HD DVD to release their movies only that format. If true, those contracts still have another year or two on them. I guess their ability to release product on Blu-ray would be determined by clauses in the contracts that handle the demise (or imminent demise) of the HD DVD format.
Regardless, as long as one of the formats emerges as the winner, and the public supports that format, there's no reason to believe that the availability of Blu-ray (or HD DVD) titles won't be consistent with those of standard DVD. The studios would like nothing more than to be able to sell the same movies, that people have already bought on DVD, to the same people, but in a different format.
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