Did you know that You Don't Know Jack is available today on Xbox 360 Games on Demand? If not, then you didn't know jack about You Don't Know Jack. And now that you know, you know you can go learn more about You Don't Know Jack, play it, and then find out whether or not you know jack about a variety of other subjects... or you could get World of Outlaws: Sprint Cars. That's the other new Games on Demand release.

The Major Nelson post announcing upcoming XBLM content also reveals plans to release a second Driver: San Francisco demo. In addition to the single-player demo out this week, next week Ubisoft will send out a multiplayer demo. We hear the multiplayer is the game's strong suit.

In other XBLM news, you can save on a random assortment of Rock Band music including Metallica, Blink 182, Lady Gaga, Bon Jovi, and Queen packs this week, and an equally random assortment of Xbox Originals (Fable, Black, Crash Bandicoot: Wrath of Cortex, and Legend of Spyro) next week. Yeah, we don't know.