Snow LeopardEven the name seems to underpromise — it’s the first “big cat” OS X codename to reference the previous version of the OS, and the list of big-ticket new features is seemingly pretty short for a version-number jump. Maybe that’s why Apple’s priced the 10.6 upgrade disc at just $29– appearances and expectations matter, and there’s simply not enough glitz on this kitty to warrant the usual $129.