I'm planning to go Quad Core within the next six months. However I am not being driven by speed as much as the ability to run a number of virtual machines and easily use them for software testing as well as providing a sand-boxed internet connection. I'll confess I also look forward to writing my own threaded programs to see if I can get speed advantages.

Its a shame that (so far) it is only possible to get a VM machine with software DirectX 8 emulation. Hopefully someone will work out a way to interface with graphics acceleration hardware without busting the VM concept wide open.