Prediction: Over 50% of machines shipping Windows Longhorn will be x64

I'm blogging this so we don't forget that I said this.  I was in a conversation with Steve Sinchak, best selling author and owner of TweakXP, and I made this bold claim:

Steve Sinchak says:
you are in a niche
Steve Sinchak says:
that's for sure
Ryan Hoffman says:
yeah
Steve Sinchak says:
we all are
Ryan Hoffman says:
but extended64 this is a rare type of niche
Ryan Hoffman says:
because
Ryan Hoffman says:
this niche will surely become the mainstream
Ryan Hoffman says:
if people want it or not.
Steve Sinchak says:
eventually
Steve Sinchak says:
there really isnt the dire need as there was when the transition from 16 to 32 occured
Steve Sinchak says:
eventually, software will be able to take advantage of it
Steve Sinchak says:
it needs the killer app
Ryan Hoffman says:
nah
Ryan Hoffman says:
almost EVERY new pc will be x64
Ryan Hoffman says:
when longhorn ships
Steve Sinchak says:
we'll see 
Ryan Hoffman says:
i am willing to bet you
Ryan Hoffman says:
that over 50% of shipping longhorn machines run an x64 enabled os in the first year.
Steve Sinchak says:
thats a bold claim
Ryan Hoffman says:
actually
Ryan Hoffman says:
i'm blogging this

So, there you have it.  Anyone want me to justify my reasoning?