So as promised: received my Macbook pro, transfered my license and was very happy to find that Shake runs just fine, faster than my older G4 powerbook. Nice that I'll get another speed bump whenever 4.1 arrives. GUI is a little slower -- particularly noticable in HueCurves, but relatively speaking tolerable.
But then just for fun I installed Parallel Workstations and Fedora Linux. Ran the VM, installed Shake for Linux and ran that in a window over OSX. Damned if it didn't load like a demon and flipbook a fileIn node maybe 3 to 4 times faster than Shake running on OSX! The GUI in the Linux VM was absolutely unusable -- as far as I understand it Linux and Windows if you chose to install them run near native in everything but graphics, which runs dog slow. Trying to zoom my script was next to impossible. But the renders sure were fast. Makes me think I should work in OSX and then set renders in the Linux VM 
But one would hope that 4.1 native universal binary for the intel chip will (maybe) approach speeds comparable to the Linux build. I suppose this is a testiment to the lean, mean nature of Linux.
The best was when someone else in the studio launched Shake off my laptop on their Linux desktop across the room.
j