It really depends on your definition of "best"
I think (not a fact!) for a total solution - motherboard chipsets and CPU's, Intel wins on the "Quality" and "Stability" fronts.
AMD are undoubtably the "best" for "value" right now, especially with the Duron CPU, that may change, as could the Intel "Quality" and "Stability".
If I had the choice assuming equal prices and Mhz I'd go for Intel.
If I was buying new right now, AMD would get my $$$ as they offer the "best" product for my needs, which is mainly gaming and internet use - and at a very reasonable cost.
There are other issues with AMD solutions such as temperamental power supplies, RAM, bad motherboards, etc etc. This also happens with Intel solutions, but seemingly not as frequently.
Remember there is no such thing as a free lunch..