Audio and rendered cutscene is what take the biggest amount of space on a disk usually, but you can easily get ride of most of those on a 2nd disk/3rd disk. With an audio compression similar to the one in FFXII, you could squeeze a lot more data than you think..A) go full out with graphcis and such so that all the towns/etc you see work for the first part of the game, and when switching to the second disk you can continue to see other towns etc, but wont be able to go to previous towns unless you want to switch disks again. This way would be more of a hassle, but you can still get the full quality out of it.
The other thing would be mapping, and I've no idea how much space they used for that in MGS4. Are you going to be able to come back in previous area? Can they compress them without losing any quality (longer loading)?
It's probably what happened, because quite frankly, 25-50gig of compressed data is huge. There is no reason not to compress thing unless you want to speed up loadingCreating 25 to 50GB of content for 1 game takes a really long time and costs a hell of a lot of money, unless you're just not compressing things. It's quite possible MGS4 is so huge because they're just not compressing the audio or any video very much. I'm sure they could port it to a DVD9 if they really wanted to. Also, some huge PS3 games are actually not really that big either. They just mirror content in several locations on the disc to improve load times. I personally don't care which consoles get which games as long as the games are good. I don't own any next-gen consoles yet btw, although I would buy a Wii if I could find one.
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