I'm going to go with the pattented...
Attach Ratio means almost nothing... as it changes with time and to make any predictions based on attach ratio is foolish... as those atach ratios will change
The Wii attach ratio SHOULD be lower because it's already cheaper, and already hitting the casual market. Lots of casuals own it... casuals don't buy much software... this never bothered the PS2 much. Of course the PS2 attach ratios are different because it didn't hit the casual market as hard and as fast as the wii did.
Not all "hardcore" owners who want one can even get their hands on a wii at the moment. I have a freind who was about as Nintendo Fanboy as could be... he was trying since it came out to get a Wii and didn't end up getting one till last week.
I expect the 360 will have a much better attach ratio and probably much better sales until the Wii outpaces the 360's console sales by quite a bit... as it will take a while for every "hardcore" gamer type to get a wii since a lot of the crazy grandmas are getting them.
Also you have to take into account that systems themselves cost money. If someone made 250 dollars to buy a wii... next year he makes about the same 250 dollars... this can go to games.
A lot of 360 owners can afford more games this year, because they bought their systems last year.
