I don't know why people think about AMD much right now. If you check out spec.org benchmarks, the Opteron 2222 machines (3.0 GHZ) don't have a prayer at beating the 5160/X6800, in either FP or INT. Especially INT since almost everything you want to run fast is INT, the video cards do all the important vector and FP math.
How bad is the fastest opteron 3.0ghz at INT?
How good are Xeon 5160s at INT?:
I also only trust base measurements, because peaks are hacks at compiler options to make code a perfect instructions mix for the CPU arch, which almost never happens in real life.
I don't know why people suddenly think AMD is competitive, its not.
Its maximum wattage outputs are far higher, they cost more and have random sockets, now its 940-AM2 and F-1207, they have a huge family of sockets before now, which is stupid (and hurt AMD, especially getting rid of 940 and 939 and working against the Opteron 1xx sales).
If you put together a gaming rig which you aren't overclocking this year and its not Intel - I feel bad for you. I have an X6800 and a 8800GTX, and I've had them for 6 months. Nothing AMD/ATI has done even registers on my radar as a remote threat. This will not change throughout this year except for the new crop of 1333MHz FSB CPUs.
AMD scales better due to integrated memory controller. This scales better when you put more than 2 sockets in a box. Who cares, no one games with 4 socket motherboards.
Intel had Netburst, which put AMD ahead - way ahead. Now Intel has Woodcrest/Conroe, which could potentially get AMD to quit making silicon if they cant catch up.
"AMD considering getting out of fabrication business"
Conroe is potentially AMD-ending event. For myself, I have a host of Intel and AMD machines at home and at work, and I can say for 1-2 socket motherboards, AMD doesn't even exist anymore.