After the current-generation console race began in earnest in November 2006, the Wii consistently outsold the Xbox 360 and PlayStation 3 for years. According to Cowen analyst Doug Creutz, Nintendo's console was outselling the PS3 and 360 combined on a trailing 12-month basis as recently as January 2010. That means that over the previous year, sales of both Microsoft's and Sony's consoles together couldn't stand up to that of the Wii.

　　Analyst Doug Creutz believes sales momentum has shifted to the Xbox 360 in the US.

　　However, in 2010 that trend began to change, with the Xbox 360 beginning to outpace the Wii on a monthly basis in the US. That trend accelerated in the latter part of the year, thanks to the introduction of the slimline Xbox 360 in mid-June and the Kinect motion-sensing system in November. The latter device has gone on to ship over 10 million units since its introduction.

　　Now Creutz thinks the momentum has fundamentally shifted. In a note sent out to investors this morning, the analyst said that when the March NPD numbers come in, the Xbox 360 will have overtaken the Wii on a trailing 12-month basis. "This illustrates the significant shift that has gone on over the last year in the console space," he said. "This does represent a share shift as opposed to just a decline for the Wii. We believe the significant shift in hardware sales towards HD consoles is a positive ongoing development for the US publishers, who earn the majority of their sales on the 360/PS3."

　　However, just because Nintendo has slipped a bit doesn't mean it's falling too far behind. In February, the Wii sold 454,000 consoles compared to the 535,000 Xbox 360s sold in the US, putting the Wii's domestic installed base at 35 million units. (By comparison, the Xbox 360's global installed base is 50 million units.) Nintendo claims that the Wii reached that mark faster than any other console.