I suspect that Microsoft "stuffed" expenses into this quarter to have better quarters going forward OR they deferred some expenses to make previous quarters look better. There are just too many hits that are significant in nature for them to be just "in the course of business". It will be very interesting to see where their R&D and such are NEXT quarter. I'd be willing to bet that they fall much more in line with previous quarters and not the last "inflated one". We'll certainly know with next quarter's numbers if they were recognizing expenses that will be "used" next fiscal or they deferred and recognized them so as not to carry them into the next year.
Regardless, I think your model works well assuming your inputs are fairly solid. You can't account for one-times that are of the magnitude MS delivered in 4Q.
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Systems I currently own: 360, PS3, Wii, DS Lite (2)
Systems I've owned: PS2, PS1, Dreamcast, Saturn, 3DO, Genesis, Gamecube, N64, SNES, NES, GBA, GB, C64, Amiga, Atari 2600 and 5200, Sega Game Gear, Vectrex, Intellivision, Pong. Yes, Pong.
