I seriously doubt its a "new city" - as the scope is too large, compared to the current game. But its also unlikely to include "no new areas".

Most likely, it would use the existing assets of the game (may even include the extra textures if needed), and you could get the geometry and other city sections in 100-200MB max (if you planned for it).

Maybe 10-20% the size of the main game city. Its still significant though - much comes down to how well MS advertise the fact, and WHAT they are allowed to say.

If it was a COMPLETELY new city (i.e. 20 missions+?), and was TRULY EXCLUSIVE to the 360 (not some 6 month time restriction), this is really major news.

Then again, they could give PS3 owners exclusive content as well later - so what, would fans then need to buy BOTH copies of the game - and two consoles?

Just do what I did and get an elite. I have plenty of room to spare.

Well for some reason most of starcraft's last forums are about how inferior the ps3 gta is compared to the 360's gta. Is the info you are giving just a rumor or does it have reliable sources because if the update was that majour than how would it fit into most of the 360's HDD without it filling up most of the HDD, and dont you think that Microsoft would have been boasting about this instead of just calling it DLC.

I find this a bit hard to believe, but it could be true... It's possible that the game's artists have had the time to start doing this a few months ago.

I say 20% probability for now;)

Seriously guys, if the DLC was that major Microsoft would be milking the f*** out of it for console sales instead of not even advertising it. If it is that big, it's likely timed exclusivity and they don't want to put their foot in their mouth by claiming they will be the only ones getting new cities and missions.

Besides, so far all I've heard official from either source is "episodic" content which has nothing to do with the main storyline of the game, or adding huge portions of city to it.

http://au.ps3.ign.com/articles/863/863450p9.html

Dan Houser said that the DLC will be worth the money paid but he also said:

"The game that you buy on the disc is the game. The extra stuff doesn't exist yet, but it exists in our heads... It's cool stuff. It doesn't undermine the individual game."

Adding what amounts to a complete game only to one system will undermine the original game. Him also suggesting the the disc IS the game further shows that they are looking at adding side missions and side stories rather than full blown cityscapes and additional main story.

EDIT: I think anything added to just the 360 in DLC will not effect the main cannon of the storyline and likely be new multiplayer modes/missions.

 The second link says as you quoted:

and the press are highlighting how massive the Xbox 360 exclusive downloadable content will be

Massive doesn't tell us anything at all, massive implies largness without giving any specific parameters. It is just an adjective that means big. How big is realative to who you ask, obviously microsoft wants us to think its this huge amount of content but they continue to be vauge enough that if it doesn't turn out as big as people think it should they can always hide behind that vagueness.

This could be possible! Especially since Rockstar has been working on the DLC since early last year. They were in dire straights last year also. The fact of the matter is if this is true then that $50 million will have paid off ten fold. Even casuals would download new installments of GTA. If they can download games off the VC they can an will download this.

Link?

I don't follow this. Does not playing VC detract from playing GTA3 then SA?