Xbox Live Marketplace - Free Halo song for Guitar Hero III, Orange Box demo

Microsoft's Turkey Day surprise was a free Halo music track for Guitar Hero III (take that, Rock Band!) and the first of a series of demos for The Orange Box:

• Arcade: Undertow ($10)
• Guitar Hero III song: Halo Theme Mjolnir Mix (free)
• The previously announced Rock Band music from Creedence Clearwater Revival, Foreigner, The Knack, Metallica, The Police, Queens of the Stone Age, The Runaways, T. Rex and Wolfmother (3-packs for $5.50, or $2 per song)
• Ace Combat 6 planes ($2.50 to $5 each) with a free F-16C -Scarface
• Phantasy Star Universe Ambition of the Illuminus expansion ($20)
• Thrillville: Off-the-Rails Booster Pack ($5) with 10 new levels
• Beautiful Katamari unlocks and add-on missions ($2.50 each)
• Demos: BlackSite Area 51, College Hoops 2K8, MX vs. ATV Untamed, NCAA March Madness 08 and The Orange Box: Half-Life 2 Episode Two
• Game Videos: BlackSite Area 51, Crash Of The Titans, Dead Space, Mass Effect, Naruto: Rise Of A Ninja and Major League Gaming (free) plus Red vs. Blue Recovery One - Part Three ($1)
• Themes: BlackSite Area 51 and Thrillville: Off-the-Rails ($1.88 each) plus Golden Compass (free)
• Pictures: BlackSite Area 51 ($1.25 each), Thrillville: Off-the-Rails ($1.88 each) and Golden Compass (free)

Microsoft also announced it will release the Halo 3 Heroic Map Pack with Standoff, Rat's Nest and Foundry maps for $10 on December 11 and then make it free next spring when the second map pack hits...