People keep mentioning that these levels are 2 gigs and 4 gigs and whatever, but saying that is very misleading.  A level is only a large (100-200 MB) text file and the reason why they can brag that they have a huge level is because of all the textures that text file references.  The thing is though, a smart developer will re-use a good majority of those textures.

So saying the first level is 4 gigs, the second level is 3 gigs, and the last level is also 4 gigs doesn't mean it uses 11 gigs of space.  They all will probably share at least almost 3 gigs of information with the second two sharing even more and only being larger because they are probably larger levels.

Surely many of these games have not been compressed in the same way that games for DVDs have, as there is no need for it. I'm sure that most of these games could fit on a DVD, if they took out a few extras. Uncharted for example, is filled with extra content like developer interviews, which I would assume take up some space because they are probably in HD. Little things like that could be removed to allow them to fit on DVD, but I would assume that most devs are getting close to running out of room on DVDs

When the 360 does have a hard drive, it does use it for cache. It increases load times for many games.

@videogirl

Bioware has stated that the game was a bit rushed to completion. That was cited as the reason why the game was not as complete as they wanted it to be, and why there were some bugs. Since it uses game graphics for all the cutscenes, it's allot easier to fit everything on a DVD.

To those who think bigger space means better grahp, I suggest them to try the famous Kkrieger ( http://www.theprodukkt.com/kkrieger ).
It's 96ko (yes !) and quite impressive.

To be a real advantage, the BR would have neede to be 2x. Right now, the PS3 BR is x1 and it's way slower than the X360 DVD.

But frankly, for good developpers, space might not be that much of a problem (except for really big worlds I guess). Visually, UDF and GeOW aren't that far. And there both streaming with no loading beyond the initial one.

Cryoakira,

Krieger is a nice demonstration, but nothing really new, similar methods have been applied to games and demos for decades whenever this made sense, there are many current and past examples. More space is needed for the long run. High quality textures and audio take up a lot of space, developers will re-use much of the already implemented technology in future sequels for new franchises, creating more audio-visual diversity (for example more levels) with higher quality for such games will require dual layer Blu-Ray discs.

On average the PS3's Blu-Ray disc loads faster than a XBox 360 can read a dual layer DVD (12x slows down to 8x, max speed only possible for the outer tracks). The XBox 360's current HD DVD drive is a single speed drive, probably about half the speed of the PS3's drive (the minimal bitrate for all BR players is higher than for HD DVD) I really have to wonder why this misinformation continues to exist, just like much other stuff I read on the internet.

Hum... Nope, it's hasen't been applied for games much, because procedural requires a high level of mastering and doesn't work with many games. Make a few seach about the subject, and you sell how rare this is.

 More space is needed in long run, indeed, but on the current gen ? Don't forget that :

1- despite all their processing power, the PS3 and X360 still have low RAM capacity, so the size of texture you can use remains low. PC games that can use VERY high rez textures and 2Go of RAM, like Crysis, still make less than 7 Go once installed on PC.

2- Because of game budget and content production costs, games are mostly even shorter than before.

And finally, on average, PS3 BR load slower than X360 DVD, on multiformat games.

DVD 12x read faster on roughtly 80% of its surface than BR 1x.

You can find datas (based on officials public specs) here :

http://img25.imageshack.us/img25/4716/dvdvsbdrs1af.png

You can also find an interesting article from Arstechnica (http://arstechnica.com/journals/thumbs.ars/2007/1/17/6658)  

with a little citation " Said Bethesda's Todd Howard, "Drive speed matters more to me [than total capacity], and Blu-ray is slower." " 

Obviously, you're the one misinformed about the subject and you should read a bit more on the internet abou it.

One thing I noticed PS3 BR runs extremely quite. Also I love how in Uncharted there is no load times (actually loads as you go).

Yea, the load times in Uncharted are pretty awesome. Sometimes you'd get texture popping at the beginning of a cutscene, but I don't think it was as annoying as Halo 2 which had popping every time the camera angle changed.

As for Krieger, it's cool that the package comes that small, but the thing I noticed is that it takes a while for it to do it's thing with the data when you actually want to play the game. Also, I'd rather see a full game using those type of compression techniques because except for some interesting little effects and such, Krieger didn't offer anything more than what something like a flash game would offer, just with decent looking 3d graphics.

Naughty dog have a tradition of doing that. No load scenes in J & D games either, although they may have had some long elevators there

It was a small (and a bit old now) project. But the interesting thing with this kind of technic is that, fully masterised, it gives a result depending on the power of the CPU. So it allow games to "age" (up to a certain point of course). I doubt we'll see a "full" game using that technics, but some games use it for specific content.

As for Naughty Dog, it's just that they're damn good (and the fact UDF is linear help a bit).