According to official NPD data, which tracks North American console sales, the Xbox 360 took 30 months to reach the 10 million units sold milestone, 20 percent faster than the original Xbox, which didn't achieve the same mark until month 36.

While an improvement, the mild increase casts doubt on Microsoft's assertion from Wednesday in which Xbox vice president Don Mattrick said: "History has shown us that the first company to reach 10 million in console sales wins the generation battle."

Assuming the Xbox 360 maintains its 20% sales margin over its predecessor, taking into consideration steady global sales, the 360 will go on to sell 28.8 million worldwide units over a four-and-a-half-year life span.

If current sales velocity and history are to be believed, the projected life-to-date sales of Xbox 360 would be a far cry from the 125 million-selling PlayStation 2, which "won" the last generation battle, and the Nintendo Wii, which has sold 24 million units worldwide in only 18 months, this after launching a full year later than Xbox 360.

Nintendo is expected to surpass both native Xbox 360 sales and the 10 million U.S. milestone within the next two months, given that the console sells approximately 500,000 units per month in the States alone.