I agree with most but not all of his points. I almost did not upgrade to Leopard. What was holding me back was a lack of any "must have it" features. I just did not see any for me, personally. What tipped me into buying was after I read a review of TimeMachine and how it worked.
Currently I use a home made NAS that I cobbled together from an old PC. It works but there is not automated backup and the fan noise from the old motherboard limits its location to the basement. With TimeMachine I can attached a FireWire drive to the mac mini in my family room and with a switch backups are less of a chore.
Leopard is a great Operating System and will excite developers more than the normal user. But these new features, although good, aren’t great due to delays and being spoiled early on. I am not dissing Leopard, but this is something that had to happen, and while it was touted as a Vista competitor, it’s more of a pretty knockoff in that Leopard won’t convince you to switch if Tiger didn’t and the ‘Wow’ factor is lacking"