Mac users who are looking to legitimately upgrade from 10.5.x to 10.6 (and beyond, where applicable), should be happy to know that Snow Leopard is recently available again in the Apple Store.
It’ll cost you $20 for the disk, but then you can then upgrade to later OS versions, which are available only through the Mac App Store, which was introduced with 10.6.8. OS X 10.8 Mountain Lion will be easy to upgrade to, with a simple download-and-install. If you can only run OSX 10.7 Lion, though, you may have a little more difficulty.
Still, it’s nice to see Apple providing at least some sort of upgrade path for cautious-to-upgrade users.