So, Microsoft is testing a "new disc format". The more fanciful of you are thinking that means "Blu-Ray". The more sensible and well-connected are thinking it's something a little more realistic.
Tech gurus Digital Foundry claim that, according to "a highly placed development source", this new disc format is simply the same old Xbox 360 disc, albeit one with extra storage capacity.
Currently, a 7.95GB Xbox 360 disc can only have 6.8GB of game data on it, because there's an inaccessible partition on the disc itself that has stuff like video code and anti-piracy measures behind it.
Digital Foundry's source reckons that the "new disc format" is simply the existing disc with this partition having "either been drastically reduced or omitted completely".
This would give 360 games a 15% boost in storage, which in some cases may alleviate the increasing (and annoying) need for Xbox games to ship on multiple discs.
We've contacted Microsoft for comment, and will update if we hear back.
Source: Xbox new disc format gains 1GB [Digital Foundry]