As a Mac outsider I find Apple pushing 64 bit as big thing in OSX (as it has done for some time) to be laughable and slightly misleading.
You're talking to the company that's still supporting PPC..
Regardless of what Apple say - they have a smaller development base so I can see why they are doing this. They'll attempt to justify this though their company image (ie being at the forefront) but they will have to learn that all their software vendor partners have to have enough time to reclaim their development costs + expected profits back from the last set of development. A large change like this is not really a selling point for those vendors thus it's a cost that they're not going to be happy absorbing as it's difficult for them to pass on to their customers..
This is partly Intel to blame with the CoreDuo.. which should have been 64bit capable.. Core2Duo is only just about 64bit.. whereas the xeon is proper 64bit.
So as you can see - there's shades of 64bit as sold by Intel...