Not for a long time. Going from 32 to 64 bit addressing isn't completely as obvious as just going from 32 to 64 bits - ie, you can't yet address 64 bits worth of physical memory on any machine at this time.

There's all manner of limitations that have to be addressed in the memory addressing architecture of x86 chipsets in the 64-bit address world, and the migration from where we are now to a full 64 bit memory space is going to take some time and a bunch of compatible migrations at both the physical hardware level as well as in the kernels of various operating systems.

Right now, most physical addresses are actually no more than 44 to 48 bits wide.