Microsoft confirms 2GB XBLA size limit

Maximum 2GB file size is no longer a legislative restriction, but a technical one
The ambiguity surrounding size limits for XBLA games is over.
Developers are allowed to create titles weighing as much as 2GB for Microsoft’s online game service.
Since the Nov 2004 launch of the XBLA service, the size limit of its games has fluctuated erratically.
The limit started out at 50MB, but in January 2007 that had increased to 250MB and – if given consent by Microsoft – as much as 450MB.
But in May the next year, the XBLA size capacity was announced to have reached 350MB, throwing into doubt whether Microsoft was still approving XBLA games as big as 450MB.

That confusion only escalated during the following months. Since May 2008, Microsoft’s Live Arcade service has seen numerous games weighing in at 700MB, 1GB and – as with C&C 3 Commander's Challenge Pack – 2GB.
Microsoft's Scott Austin has, finally, put a pin on the size limitation.
Speaking to IGN, Microsoft’s director of digital games explained that legislative restrictions on XBLA game sizes no longer exist.
However, there is a technical limitation on XBLA game sizes – 2GB – which cannot be surpassed. And thus, 2GB is the final, universal, and only size limit on XBLA titles.

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