How can an AMD processor be more mobile than an Intel processor? The AMD could be the size of a 50 cent coin and the Intel could be the size of a mouse pad; as long as they fit inside the same chassis they are equally mobile. All processors termed as 'mobile' are bastardised second cousins of mainstream desktop processors and there is little in the way of performance difference between the two brands in the middle area of the price band. Any AMD Turion or Intel Core supporting the x64 instruction set will get the job done in a very similar fashion and you wont see any measurable difference in day to day use.
Power consumption largely depends on the configuration of the laptop itself and the demands you place upon it, not on the processor. I have three laptops all in differing configurations with different processors (Pentium 3, 1.13Ghz; Pentium M 1.87Ghz; and a shiny new Turion64 X2 which I use at work) and if I unplug the AC adapter and use them for office tasks, I get roughly 3 hours out of each one with the display brightness dimmed. If I unplug and fire up World of Warcraft, I get a half an hour. There is shit all difference between the brands; the size of the manufacturing process across the range of processors has the largest bearing on heat output, and not power draw, in real terms.
The specs that Jake posted look pretty sweet. The only real thing I would mention is try and get a few extra batteries. My Pentium 3 laptop couldnt even be fired up for a while without the AC plugged in (it ccould be disconnected after boot) because of battery issues. Remember every battery, just like any other rechargable device, has a limited number of charge cycles before it goes tits up, and computer companies dont often stock batteries for old models. I eventually found a compatible battery for it on eBay but your mileage may vary.
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