Actually, if you do a comparison of Price/Performance (from NewEgg.com prices), the AMD Phenom comes out ahead of the Q6600. According to my rankings (25% NewEgg rating, 25% SYSMark 2007 Score, 25% Multimedia Multitasking, 5% Multimedia Encoding, 15% Photoshop 2D work, 4% 3D rendering, 1% games, 0% power consumption), the Phenom 9500 delivers 84% the performance of the Q6600 for 78% the price. That means it's cheaper, and a better value. But that's just according to my rankings.
Tom's Hardware also ranks the 9500 ahead of Q6600 for price / performance.
So sure, the Phenom 9500 delivers less performance, but it's also cheaper. Go figure, the free market works.
The worst-case scenario for the Phenom 9500 vs. the Q6600 is 3D rendering, where performance is 76% of the Q6600 (according to equally weighted: Cinebench 10 3D Performance 1x CPU, Cinebench 10 3D 4x CPU, 3dsmax 9, Lightwave 9.5 dirty_build_render, Lightwave 9.5 record_player_render, POV-Ray). So the Phenom 9500 is going to take 1.32 times as long as the Q6600 to do 3D rendering. It's not like it's a 2-fold difference.
In games, the Phenom provides 88% the performance of the Q6600, for 78% of the price.
The other thing is that I think right now, AM2+ motherboards are better than the motherboards compatible with the Q6600. They often have PCI-E 2.0 affordably (under $200), and the Gigabyte M/B's in the 790 series support up to 16GB of RAM. These are 4- or 5-star rated M/B's. On the contrast, the only 16GB or greater M/B's that support the Q6600 have crappy NewEgg.com ratings.
And what about PCI-E 2.0, PCI x1, SATA, eSATA, Firewire? If you want to find Q6600-compatible boards that support all that, you're looking at $200 - $350. Whereas:
$149: K9A2 Platinum. 4 PCI-E x16 2.0 slots, 1 PCI-E x1 1.0 slot, 2 PCI slots, 8GB max RAM, 1 PATA, 6 SATA, 2 eSATA, 10 USB, 2 Firewire) can be had for $149.
$168: GA-MA790FX-DS5 . 2 PCI-E x16 2.0 slots, 3 PCI-E x1 1.0 slots, 2 PCI slots, 1 PATA, 6 SATA, 2 eSATA, 10 USB, 3 Firewire, max 16GB RAM.
Find a Q6600 motherboard that gives you all of that for below $180. There's more to computing than gaming and CPU power. Also think about how many hard-drives you can upgrade to, external drives, RAM, etc. And about value. In terms of value, the Phenom is a better value for your money, in terms of performance per dollar spent, and that's before even considering the superior options you can surround it with due to the better motherboards in any given price-range.