Nope, not at all. People said the same thing when we started moving to 32 bit.
Microsoft has stated that Windows Server 2008 will be their last 32 bit OS. The time is coming.
Craig,
I actually have to side slightly with Walter on this one. WS08 may not even be out until 2009, and then you have the 5 and 5. Maybe this is a matter of degree...