Hi, I had a question about the design of a mac pro. Clearly, they're the choice for someone who'd like to upgrade their machine as time goes by. My question is, for the current design of the MP computers, how well does the logic board scale? Specifically, I was wondering if there were physical differences between the logic boards in MP models with one or two processors. Does the single-processor model contain an unused space for an additional processor, allowing it to be upgraded from 1x to 2x? Or is something like this just unheard of in the hardware world? Furthermore, what future expandability does the community see for the Nehalem model of processors. Will the socket type continue to be used well into the foreseeable future (say, 4 or so years) by future processors? If I purchase a Mac workstation, I'd like to be sure of the details for what is arguably the most static element to their modular design--the CPU. Sorry if any of this is noob material, I'd just like to get my facts straight. Thanks!