I'd like to suggest a field to indicate the region encoding of a game (not just release region), as well as the display resolution supported. The past few years, I've found myself digging very heavily into differences between versions, as well as importing games, and it would be fantastic to be able to indicate this sort of thing.
While it doesn't impact me much personally, it might also be nice to indicate whether a game is locked at 50Hz, 60Hz, or selectable between 50/60Hz. Not so much of an issue on HD consoles, but for EU PS2 owners, this could be really really useful.
There's a certain potential for abuse, mainly from people who don't know anything and just make a guess based on thinking something "looks" 480p when it's 480i, or assuming all Xbox 360 games are locked (they aren't), but I think the benefits would be substantial for people like myself who actually make use of this information.