Greetings all...I am a 20+ year Windows user that has recently purchased a Mac Book Pro. I am slowly becoming familiar with the Mac OS X UI and liking it. Enough rambling...my main question(s) regarding the Mac Pro: 1). Do you think the Mac Pro can be updated at a later date with a new, improved, motherboard? 2). Does the form factor for a Mac Pro Motherboard typically change? I frequently in my Windows life would upgrade motherboards (ATX) to get performance improvements that become available with new processors/memory, etc. Just want to see if the Mac community thinks this could be possible with the Mac Pro. It would kinda suck if I had to purchase a new case, powersupply, hard drives, etc to get access to new processors, memory and such. Any thoughts are appreciated.