I've had both in the past with no problems from any... but I am not a "power user".
The way it was explained to me, AMD always makes chips that are comparable to Intel in speed and performance. But I was told that there is a difference in how they handle instructions... like there is more than one way to plumb your house and still get the brown water to the sewer.
That is why some softwares say "AMD Optimized"... because they were written to take advantage of that chips instruction handling.
To really make your decision, look carefully at your software to discover if the manufacturers suggest one chip over the other. And also, I believe Microsoft writes all their stuff with Intel in mind.
Additionally, be aware that different tasks place different types of demands on the chip. This article is over a year old, but it shows many different parameters to consider.
http://reviews.cnet.com/4520-10442_7-6389077-1.html
ymmv.