Its software that allows you to copy game cds to your hard drive (Alcohol 50%) and even make copies of them (Alcohol 120%). It can help load times since your hard drive can transfer data faster than even a DVD drive. Its $50 for the 120% which includes %50 (which I think is $35). I only use the hard drive copying really, although I can verify the copying works. You can even do this with PSone and PS2 games. I know there is other software that does the same thing, but I took a chance with this and I'm satisfied with it. I would recommend it if your wanting the extra edge and don't want to have to worry about CDs. Not sure how much of a performance gain it really offers, but Halo loads levels really quickly for me (combine this with a Raptor and it'd probably make quite a bit of difference in loading).
Oh and as for Intel's 64 bit CPU. I think I remember reading that it was supposed to debut later this fall in their Xeon's and then trickle down, but something about it might be pushed back. No telling really with Intel. They're probably gonna make sure they don't suffer another Prescott (Dell has even started putting Northwoods back into their higher end computers instead of Prescotts). Windows 64 should be out this fall, so maybe MS and Intel have some kind of a deal. I do know that Athlon 64s are known to be better at gaming than P4. The 64 bit Intel's pretty much just rip off most of AMD's design, but still have some pretty big differences (memory controller still off chip), but there's no real timeline for it, so I wouldn't wait for it.
If possible you might wait til midsummer (I believe this is right) when PCI-express and various other motherboard innovations come out. It'll offer even better gaming performance. Intel and AMD also are both set to release new socket types (775 for intel, 939 for AMD) sometime this year, so again if you can wait, it'd probably benefit you. Ideally this fall will be a great time to get a new system as the graphics will be on their first updates and 64 bit of windows will help AMD some.