The Mass Effect 3 multiplayer demo requires you to have a Gold subscription because, well, it's a multiplayer game and that's how Xbox Live rolls. Not to worry. Microsoft is giving away " a limited time Gold access" pass to everyone who downloads the demo, meaning we can all get in on the action.
No word yet on how long that "limited time" will last, but it's likely to be a weekend pass, same as you get in a game insert or on free weekends.
No info yet on how Silver subscribers will actually get access to a Gold-only (at least for a week) demo either, so stay tuned for that.