The details aren't as clear as we'd like them to be, but somehow users enrolled in Microsoft's Dashboard Beta program managed to download the Mass Effect 3 singleplayer and multiplayer demo early… in November… and the demo isn't out until next year. Wha… how?
Coming in at 1.8 BG of data, users were able to play the single-player demo and poke around in the multiplayer menus. Did you catch this while playing online last night? Send in any screenshots you've got and we'll plaster them all over this page with your name on it!
[Source]