I can be a bit more specific..
They like looking at fake, synthetic benchmark numbers and throwing those around, but there is something else I've noticed about them.. Disk access. Loading times.. Terrible. Horrible. Aggravating. Consistently bad. Every single one of them that I've seen have had this problem.
So yeah.. Performance of them is crappy (unless you overclock them maybe.. but should you really have to push it out of spec to have it perform like it should?) and data i/o is crap.
Yup. Hate them. Crap. Junk.
Not trying to start anything, or pretend to be a pro (chances are you're smarter than me in thes stuff, I admit it), but disk access and loading times... don't sound too much of a processor problem (to me, anyways). Unless someone tells me how CPU (significantly) affects disk performance or anything along those lines, I'd probably rather believe that every single AMD chipset you've come across had just been a flop or other piece-of-junk. Got a sempron here, at the time this comp was the cheapest in store, yet it doesn't load any slower than I'd expect any "normal" computer to.
For comparison, I have two exact same CPUs (P3 866mhz coppermines) on different mobos, i810 and some ASUS cheapo. Even though the ASUS comp's got double the memory (512 vs 256, same speed PC133), the i810 totally destroys the ASUS machine in just about any app&game. I still haven't figured out why - played around with memory timings and whatnot to the extent BIOS allows me to. Two old computers hardly do for comparison, but my point is that you can't always blame the CPU...
Even though we've clearly seen what intel can do, I wouldn't spit on AMD since they've done a great job creating something new rather than sticking to what's been around for decades (FSB, onboard memory controllers, whatnot). True, intel destroys AMD and AMDs recent CPUs have been a flop and they just can't seem to put up a decent fight, you might want to say that AMD sucks, is a piece of junk, crap, whatever...even if this was the truth, we owe them something. After all, If AMD didn't exist, we'd probably still have comps with 286s in them and a massive 512KB RAM! Good luck playing Crysis, people! (Help! Help! I'm playing Rogue and only get 0.0013fps...can anyone help me?)
P.S. I am no fanboy!