I think NDP is accountting for the "Financial Crisis" in their extrapolation... Likely the reason SW is so low. I think they are wrong... I have friends in retail and many things are moving slowly BUT Videogames and HDTV sales are better than ever.
End of 2009 Predictions (Set, January 1st 2009)
Wii- 72 million 3rd Year Peak, better slate of releases
360- 37 million Should trend down slightly after 3rd year peak
PS3- 29 million Sales should pick up next year, 3rd year peak and price cut