If we are specifically talking mobile applications, then the Intel mobile processors have allways had better power management for a given performance level. The new "Centrino" mobile processors seem to be even better, as well as giving "more bangs per clock"; the clock rates seem quite slow but the real-life performance is still very good. As it's newer technolgy, then naturally they are relatively expensive. AMD almost always win on "bangs-per-bug". If battery endurance is not an issue then the software compatability issue is the only possible "gotcha".

f.y.i. I'm running an Athlon 1700XP at home, no worries, but then I'm not using any special stuff (other than Sonar / Soundforge).