hi habran,
64-bit certainly is the future, but 32-bit will be around for a long while. I am still using 16-bit apps, even on a Win7-64 system in a VM.
As to speed, it still has to be proven that 64-bit apps are faster. You rarely run out of registers, especially in fast innermost loops that won't call slow Win APIs. And 64-bit code eats up cache, so on balance it's hard to prove that 64-bit code is "faster". Of course, there will be quite a number of applications that can be done faster, e.g. for videos or image processing.
But the transition 32->64 cannot be compared to the (still incomplete) 16->32 bit transition. When porting 16-bit code to 32 bits, you get a huge speedup, and the address space jumps from a tiny 65K to 4 gigs. To visualise that step: a typical 500*600 pixel JPG fits into 65k (so 16 bits of address space are indeed a little bit tight :(). The largest Hubble image so far is 15852*12392 pixel, that requires a 3x2.5 meter screen. To fill the 4 gigs of 3-bit mode address space, you need a 180x150 meter screen. I can afford my notebook, but I cannot afford a screen as large as two football camps...
Now try convincing me that two football camps are not enough ;-)