It took two friggin' years to move from CodeWarrior to Xcode so they could get 4 million lines+ of code just to compile as a Universal Binary under Xcode ...
I feel better about the product I work on having 2.5 million lines of code now. :-)
I understand the challenge Adobe face for migrating to 64 bit on OS X; for those not in the software business changing the user interface code AND moving from 32 to 64 bit at the same time is TWO (2) big jobs.
You want 64 bit computing? Get a CS4 Win license and Vista 64 (don't even screw around with XP 64) the MacPros run Vista really, really fast...
My experience -- which appears to be somewhat unusual -- is that Vista is far more stable than OS X. That plus Apple's, ah, "less than ideal" idea of hardware service means my future machines are likely to be generic PCs, but that will cause me grief trying to migrate Adobe licenses. :-(
My wish is for Adobe to do with CS4 what they've done with Lightroom, and treat a licensed copy as a licensed copy whether it's installed on Windows or
OS X. Then at least I'd only have the grief of having to use Windows, virus protection, et al, but could move as and when I wish (e.g. a new desktop at a different time from a new notebook).
P.S. I'm no advocate for Microsoft, and I've found bugs (minimum) and crashed (usually) any operating system I've ever used. Why Adobe thinks locking people to Windows who want to migrate to Apple or locking people to Apple who want to move to Windows is a competitive advantage I do not understand. Maybe I lack the requisite marketing clue.
P.P.S. If Adobe *really* want to get a clue, they could start matching their USD$ prices in other markets. Just sayin'.