Those that downloaded Red Alert 3: Commander's Challenge may have noticed that the game is huge for an Xbox Live Arcade title, weighing in at 2.1GB. Over the years, XBLA games have gotten bigger and bigger, with Microsoft slowly making exceptions to the size limitation rule so that important releases could ... well, release. Now that size limit is, for all intents and purposes, gone. At the same time, XBLA games can't get any bigger than two gigabytes. Confused? Scott Austin, Microsoft's director of digital games, told IGN that the XBLA system actually can't accept anything larger than 2GB. Some may be tempted to cry foul, as Microsoft already offers significantly larger downloads with its Games on Demand service. However, according to Austin, Games on Demand uses a different file structure. We'd be remiss if we didn't point out that Commander's Challenge is slightly above two gigabytes (while it's listed as 2GB on Xbox.com, it shows up as 2.1GB on the 360 HDD). We've sent this little puzzle to Microsoft, in hopes that we might get some more concrete details. We'll update this post when such details arrive.