Nintendo's Wii sales have bested those of Microsoft's (MSFT) Xbox 360 and Sony's (SNE) PS3 for over two years. Nintendo has begun to lose that lead as its rivals have cut prices. Microsoft and Sony will launch motion-sensitive versions of their products soon, which will make them even more competitive with the Wii.
We still don't know whether gamers will buy 3-D devices. The technology has begun to have some success in theaters and a number of 3-D television monitors will come to market in the next year, but the size of the consumer base for the technology is untested.