If you are trying to be "kinda smart" you shouldn't buy brand spanking new technology. Leave the manufacturers time to work out kinks, leave time for yourself to verify viable benchmarks, etc.
That being said, the next few months will be exciting because Intel and AMD are BOTH releasing new chip architectures. While I haven't seen any precise, or viable tests yet, it is rumored that the Intel chips simply p0wn AMD by a landslide.
The Intel chip, a 65nm Conroe CPU running at 2.6Ghz is supposed to be faster than an Athlon 64 FX-60 OC'ed to 2.8Ghz. But as I said, rumors.
Also, down the road, if ever, AMD is talking about something called "Anti Hyper-Threading". Instead of making one processor act like two, as in Intel HT Technology, AMD would make fore or more processor corse be seen as one by the OS. The technique would give the most benefit to single-threaded applications, which currently get no benefit from dual core.
There is a lot coming down the pipe, and as has been said you'll be waiting forever if you want newest stuff. You also have to look at the cost difference between brand spanking new and then just behind, versus performance gain and shelf life.