I'm currently in Seoul, South Korea assisting with the first 64-way, 64-bit deployment of SQL Server in the world.  The 14 and 1/2 hour flight has left me extremely jet-lagged -- I didn't sleep a wink on the flight.  I got here last evening, went to bed and slept for about 5 hours, then woke up at 4:00 a.m. local time and couldn't go back to sleep, so here I sit :-).  These are heady times for 64-bit apps, and they remind me of the shift we saw from 16-bit to 32-bit way-back-when.  Someday, in the not-too-distant future, everyone will be running on 64-bit machines, and we won't think anything of it.  The 32-bit model, with its 4GB constraint and hackish workarounds, will seem like a distant memory.