Unfortunately, I'm in the same position as you.
By next week I will have all the parts for my new computer except for the CPU. The Quad core is nice and readily available, but a lot of its power will not be utilised since not many applications/games are optimised for using more than 2 cores. On the other hand the E8400 is clocked at 3 Ghz per core, compared to the 2.4Ghz of the quad, can be easily overclocked and at the same time runs cooler and requires less power. The only problem is that it cannot be found anywhere
. At one point I also contemplated the option of choosing a lower specked and cheaper one such as the E8200 or even the E6750, but then desisted.
In the end I think I'll wait for the E8400.It's really a shame, especially when considering that my 8800GT is crying to be used.
P.s. It's unbelievable what happens to prices when there is scarcity. One store I consulted was ready to delivery it by next week at the reasonable price of 360Euros ($550)
Theory is when you know something, but it doesn't work. Practice is when something works, but you don't know why.
Programmers combine theory and practice: Nothing works and they don't know why.