"Same for the OS, on the Mac they've tested and considered it far deeper than Windows, and if you watch an experienced Mac user with a reasonable system, they can fly through stuff at least as fast or better than a similarly experienced PC user with a system of the same value."
My experience has been the exact opposite. I often have said anything you can do on a Mac, you can do faster and cheaper on a PC. That's coming from a Mac/PC household of over 17 years. I have been in the trenches with both systems, literally fixing and repairing many hardware and software issues from both. Despite the hype that it is *easier* to use a Mac, I have found neither OS is immune to stupidity and or planned obsolescence by design. The examples are too many to get into here.
After using the very first Mac in 1984 and several Mac systems since then up to System 9, I have found nothing spectacular about Mac OS 10. I think your statement is relative to the ability of the individual user and their level of experience with the given OS. I know many a photographer who use PC's for extensive and heavy post process work load in both Lightroom 3/4 as well as CS5 PS with a PC. I doubt there are any here that could work any faster or "easier" just because they are on Mac OSX. It used to be, pre-Windows XP Pro SP3, that there were many advantages using a Mac both from a system perspective and of the specific ports of Photoshop, Illustrator and other image editing/creating programs. But times have changed, lines have blurred and the operational advantages Apple once could claim simple do not exist anymore, other than the particular bias and sense of familiarity the end user has with their Mac.
But at the end of the day, like your camera/lens/medium, use what makes you happy.