Questions for the hardware gurus

[hgm]

I have a Core 2 Duo now (E6600), but as it seems I need it more than 100% of the time, I consider buying yet another system. I considered buying a quad (the same system as I have is now sold for the same price wth a Q6600 in stead of an E6600 CPU), but I also decided to wait for the 45nm version of it, and perhaps buy a system with two such CPUs.

I really would like to so some SMP stuff, but for 2 or 4 cores it just doesn't seem worth the trouble. I'd like to have 8 or 16 cores, only there you can see if the algorithm you are using is any good. So perhaps I should even wait for Nehalem, which is rumored to be designed for having octal core, and support hyper-threading, so you could use 16 threads.