Considering AMD's new processors are on the horizon and Intel currently has the performance crown, one might be tempted to answer "no." That said, AMD's chips do offer rather good value in the sub-$150 price range, and the company's next-gen Phenom processors will be Socket AM2-compatible. In TurtlePerson2's thread, a few gerbils recommend either waiting or going with Intel hardware instead, but others like riviera74, PerfectCr, and torax suggest upgrading to Socket AM2 now may be a decent option.
What about you? What's your take? Would you upgrade now, buy something else, or wait? If you have something to contribute, feel free to hit the thread and reply. You'll want to register for a forum account if you don't have one.