AMD's Phenom FX will be their attempt to get back into the “performance” market, which the Core 2 Extreme is enjoying almost to itself at the moment. The processor, much like the Phenom series itself, has been sadly long delayed. We're now hearing that the CPU will be available in early 2009, which will put them still quite behind Intel. Depending on how much further Intel can advance the Core 2 and Core 2 Quad line by then, the delay may not mean a whole lot from a performance perspective. Between now and then, though, anyone looking for the cream of the crop is likely going to swing towards Intel.
The CPU will have many attractive features about it, such as a 45nm process, 4 native cores rumored to be upwards of 3GHz (still an advantage over Intel's current Quad design) and itself coming factory unlocked. It's a shame they are taking their sweet time in getting these parts to us.