Last time I looked into this there was much confusion about posting a small yearly profit (which they've done for the last few years) and actually having a positive return on the umpteen billion dollar investment they've made.
Various figures I looked at then (maybe 6 months ago) suggested they were still 1-10 Billion in the hole overall with some hope that they'd break even after this generation, though obviously the model they've followed means another giant investment at the beginning of the next round of the console war.
Can you find anything to suggest that the XBox project as a whole is in the red or black for Microsoft?
With so many xbox 360 users out there who will keep paying for Xbox live and buying new games and further innovation (Natal) and more features (Hulu integration) I suspect Xbox division will be profitable for some time.
Also, the numbers include money "invested" in kin and windows phone 7 so Xbox alone is probably making more money than the numbers suggest