You can run a 64 bit kernel, with a 32 bit userspace BTW, this lets you access all the memory on your machine.
Personally I'm waiting for debian multiarch to switch, since I have no desire to reinstall everything from scratch. If debian multiarch did not exist I might have bitten the bullet, but since it does, I can wait a bit for it.
But those are still bleeding edge options for people comfortable with tinkering with their systems. I was speaking to the simple choice of i686 vs. x86_64 in pre-cooked systems.