Quoting Thrax

AMD is recommending a motherboard that tips the scales at $180 for the X4 955. That's not cheap, and it's in the same price range as any number of high-performance X58 boards. Comparing the cost of AMD's recommended motherboard with a 955 to one of those X58 boards and a Core i7 920 reveals that there really isn't an unbridged chasm in platform value.

Not entirely true. AMD's list of recommended mobos have prices starting at just under $100 and peaking at $190. And you can't get a good Core i7 board for that. The Gigabyte X58-UD3R and DFI X58-T3eH6 are the bottom two enthusiast boards; the Gigabyte is slower than most but overclocks well, and the DFI is hit-or-miss. The core of enthusiast boards seem to start in the $240 range and go well over $300.

If you cheap out with a 955 build, you're $245 + $120 + $30 (2GB DDR3-1333) = $395
If you cheap out an i7 920 build, you're $288 + $180 + $50 (3GB DDR3-1333) = $518

The question becomes, does the 25 percent increase in cost to go to Core i7 give me at least that much performance increase? That's where the value argument takes place.

But most of us don't want systems that are shady tweakers. We want the fancy motherboards, fast memory in large capacities, and the whole enchilada. If the prices for the best AM3 boards fell like the prices for the nice Core i7 boards have, perhaps they'd have a chance at this system level, but in reality, the difference still is around $100. And when you're talking overclocking systems, a 4GHz Core i7 will rock a 4GHz Phenom II. Without a boost in clock speed, the Phenom II will remain "that chip that the LN2 guys use"