Intel is like buying brand name clothing, it cost a lot more but it looks the same as another not as known brand.
AMD has great processors, but intel has the fastest (for an outrageous price) Some people believe AMD's over clock better, which I believe.. I have my 2.6GHz dual core OC'd to 3.1GHz with 100% system stability (fan cooled)
AMD can sell you the same speed processor as Intel for around 40-100 dollars less.
But Intel has the fastest processor on the market. (But, AMD has the fastest Graphics card on the market haha)