QUOTE(mlapaglia @ Dec 22 2006, 08:08 AM)

but in the past did any console have a year head start? lol
Yes in nearly every generation actually
NES had a year on the SMS and won
Genesis had a year on the SNES and lost
Saturn had half a year on the PSX and N64 and lost
Dreamcast had nearly a year on the PS2 and lost
PS2 had a over a year on the Xbox and GC and won
There are lots of metrics people have looked at to predict patterns in the game industry as to who sells the most units each generation... there are only 2 metrics that hold true
1. The first console to reach 10 million units is the one that outsells all of the others in the end
2. The console that has the Final Fantasy Franchise is the one that outsells all of the others in the end.
This generation is interesting because it looks like the 360 will most likely hit 10 million first. while the PS3 will most likely retain the Final Fantasy franchise. so we'll see which metric holds the most truth.
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As for groups like NPD, Nexgenwars and VGCharts... they are ALL inaccurate.
NPD is useless because they don't track online sales (which makes up a substantial portion of sales these days) and they also don't track some larger retailers like Walmart (which also makes up a substantial portion of sales). Actually they only track sales of very specific retailers... which can really skew results.
VG Charts is mostly using NPDs already flawed numbers, in addition to hand selecting particular news releases, which is even worse IMO because then it throws personal bias (sub-conscience or not) into the mix.
Nexgenwars goes almost entirely by news releases...