I’d hold off on Mac OS 10.5.3 Leopard if you need to use your computer as a production machine. I have had pretty good luck with 10.5.2 and CS3 but there are still some “issues”. (See above)
It appears as though there are some big minds working on things behind the scenes but “man o man” I wish Adobe and Apple would at least adopt an open-source bug-fix timeline scenario. This would help mission critical workflows from being sabotaged. Both Apple and Adobe have put out documents saying they are compliant with each other but alas there are show stopping issues that still need to be ironed out. As always, finger pointing from Adobe and Apple. Who on our end can tell (or care) who is at fault. Just get it done, hit some deadlines and make the grade. You are embarrassing yourselves and us.