Last Week, Afterdawn.com says (in Gears of War 2 sells 2.1 million units on first day) It's November 7th release puts another blockbuster on the shelves alongside the Xbox 360 console for the holiday season. Later this month Microsoft will push out a system update for the Xbox 360 that will completely change the user-interface of the console.

And TG Daily says (in Gears of War 2 hits 2.1 million units on day 1 – report) Afterdawn.com
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Halo 3 was capable of more than doubling Xbox 360 unit shipments: In August 2007, the month prior to the game’s release, Microsoft shipped 276600 Xbox 360 ...
Gears of War 2 sells 2.1 million units on first day Afterdawn.com
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And tgdaily_all_sections (Feedburner) says (in Gears of War 2 hits 2.1 million units on day 1 – report) It appears that Microsoft had a blockbuster title in stores just in time for Christmas once again. Gears of War 2 could not quite match Halo 3, but 2.1 million boxes sold on day 1 means that Microsoft’s game studios and Epic received an early Christmas present and the Xbox 360 should see a nice b...

And Kombo.com says (in Early Reports: Gears of War 2 Moves 2.1 Million on Day 1) According to early retailer reports, and user polls, Gears of War 2 is shaping up to be one of the biggest <b>Xbox 360</b> titles to date, putting it in very similar territory to blockbusters '<b>Halo 3</b>' and 'Grand Theft Auto IV' Using the <b>...</b...