I noticed that while Halo Reach sold 952k and Halo 3 sold 908k first week, that doesn't tell the whole story. According to Wikipedia, Halo 3 launched in the EU on a Wednesday (September 26th, 2007). We know Halo Reach launched worldwide on Tuesday (September 14th, 2010). I just thought this was interesting, because it means that on a day-by-day basis, it would appear that Halo 3 probably actually sold practically exactly the same (or perhaps a little better) than Reach has. I know that we can only take first week sales as is, and I'm not trying to suggest we should consider Reach to have gained some sort of "unfair advantage" or anything I like. I just think it's something to consider when looking at the lifetime sales, because it's quite possible (probable, even?) that first week sales for Reach will make up a slightly larger portion of total lifetime sales than for Halo 3, as the opening week was slightly longer. Just food for thought.
Great Reach (and 360) sales though. The 360 is certainly in demand, and a full-fledged Halo release was probably the best thing Microsoft could possibly release to sustain/increase sales (other than some massive, must-have, new IP or something).