Its a question of hardware as well as software. They sure don't give a new Mac away. I have excellent hardware (Beige with G4 processors) that does what I need it to do (CAD) and works well with OS 9. I'd love to be able to take advantage of many of the new software offerings for OS X ... but my Voodoo 5 isn't supported at all and most likely never will be, and the new quartz extreme graphics engine won't run on any PCI graphics card ..including the only Mac compatible PCI card still being produced .. even though its AGP bretheren is.
Now if the hardware support is broadened to include more older (and perfectly functional) hardware. I'd load OS X tomorrow.