Andy, if I can spend the bucks to upgrade a wheezing circa-1995 7500 to OS X, you can too. There is no plausible advantage to developing for 9 and the user base is shrinking. The user base of legacy Macs that cannot be upgraded to X is even smaller, and I doubt much of them are using 3D software intensively. Let's leave this issue behind and not hamstring CL's development cycle. If you're having trouble upgrading your Mac let me know and I'll offer some advice on solutions.