Excellent post and glad I stumbled upon it now
As I'm in the process of buying a new near bleeding edge PC for multimedia etc work and am choosing Dell's XPS Studio w/ the i7 processor at 2.66G and 4GB of DDR3 memory and Vista home premium 64 unless I can get it loaded w/ XP Pro still even though Windows 7 is just around the corner.
I have spec'd it w/ the stock integrated Intel (I think)7.1 audio for now but have an ATI Radeon 4850 HD graphics card w/ dual monitor support and DVI etc w/ 512MB RAM for video (made by Diamond, but uses the ATI chipset) and a 500GB, 7200RPM SATA HD and a 21.5 full HD widescreen monitor and will find out how the CD's come before I purchase and try some of your suggestions. I am also getting Office '07 pro and it's pre-installed. Later I plan on adding a RAID array, stripped for HD editing, a blue-ray recordable etc drive and an alalogue/digital capture/video card for video editing and will get a good audio card.
But do have a curiosity, what are the differences/similarities between the i7 and the Xeon used in the G5 Pro, other than the XEON is actually a server processor.
An IT guy says the XEON is overkill even for HD video but liked the i7 processor though and know it leapfrogs the mainstream duo core2/quad processors.