Thinking of going core2duo or AMD 64 X2? Forget it! Bit-Tech just published an article called "Don't Upgrade Now - Quad-Core is coming soon!" Here's a bit:

The other Core 2 Duo processor that really caught our eye was the E6600. Intel's list price for the chip is US$316 - this is a little more than the Athlon 64 X2 5000+, which looks set to sell for around US$282. However, the advantages to spending an extra $35 are simply massive - the 12% price increase is worth over 20% in terms of performance. Considering this, the E6600 would be my choice when it comes to D-Day on the 24th... if it wasn't for Otellini's revelation yesterday.

In light of this, if you're desperate to build a machine based on Intel's Core 2 Duo processors, I recommend that you spend as little as possible, saving your money for the quad-core upgrade later this year.