http://www.gamesystemwars.com/

[Shayne]

Went up 400K due to the release of the Wii in Japan

[Lazybones]

Went up 400K due to the release of the Wii in Japan

Ya that would be a factor as well

[Thorin]

www.nexgenwars.com now has a little chart at the bottom showing how sales have increased over time.  Unfortunately there's no x-axis label for time, just a y-axis label for units sold.  Still, handy now that Shayne's no longer screen-scraping and publising the stats.