it probably would "pop" right in perfectly well. The question is whether or not the bios would work properly with it. But, right on that register article was another link to the answer of a question being asked about alot: AMD & PCI-E. Check it out!
1.1ghz isn't all that bad either. I mean, to put it in perspective for a Centrino around 1.1ghz you're getting performance around a 2ghz P4 or higher. Except in this case you're getting 8 hours of battery life on a tiny battery, instead of less than 1 on a huge battery with a P4.