Also bear in mind that the Bluray - DVD thing is a two-way street as far as games are concerned. Bethesda said they had to store content on the Bluray in triplicate for the PS3 version of Oblivion, because the BD-ROM's access speed was so much slower than a DVD (effectively cutting the Bluray's capacity to about 14Gb - just to reduce the seek time). So greater capacity in exchange for longer load times? Looks like Bluray vs Multi-DVD isn't straightforward.
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