Nice numbers.
But I guess if you visit here often you will know of the flaws in them, like a lack of a Christmas period each year, and sales will likely slow down for x-box next year compared to PS3, and PS3 may slow down the year after but also may last a year longer ('last' being used to indicate significant sales, not the total lifespan)
Many other factors too, and some of the Sony fans might be in here with lists of game releases that will supposedly increase PS3 sales massively.
Personally I think the 360 number you ended up with seems pretty good, perhaps the balance of no Christmas sales, but no drop off in later life worked each other out.
I expect about 35 million for 360.
I expect the PS3 to almost certainly sell over 50 million, perhaps ending in the late 50s
