Well, I own both, but if you're in to investing short term to make a quick buck, I wouldn't buy either one. On the other hand, if you're looking long term, then both are probably buys. Intel is a bit stronger buy because they are so much more diversified now, and because they are so big (being a part of all three major stock indexes requires a lot of funds to own Intel, ie. funds based on these indices). Long term I look for Intel to move further and further away from a CPU-intensive company towards being more of a specialized fab company + some other areas. I think Intel is going through a transition similar to when they bailed out of the memory industry and started concentrating on CPUs. They won't get out of CPUs entirely, as their server business is growing much bigger, and that's were the CPU earnings are really fat. But Intel is spreading out with things like their StrongARM chips, the new DSP that they will soon release, hosting, networking, and several other lucrative areas. They also have some very important alliances with Cisco and Ericsson that they will build upon.
I'm not as positive longterm with AMD as they don't have much besides CPUs and FLASH, and in FLASH they have so many competitors (Intel, Sandisk, Samina, etc.), that once the shortage of FLASH is caught up with, I think FLASH prices will drop a lot. But FLASH ought to be strong for at least another year.