Apple's offering a free upgrade to Snow Leopard to any MobileMe users who are a little out of date.
Since MobileMe, Apple’s subscription-based set of online services, is being discontinued by June of this year in favor of iCloud, Apple’s offering a new deal for MobileMe subscribers. As iCloud is only supported in Snow Leopard and Lion, Apple is offering all current MobileMe subscribers a free hard copy of Snow Leopard.
If, for some reason, you still haven’t upgraded to Snow Leopard yet and you’ve been using MobileMe before subscriptions closed last year, now’s the perfect chance for you to save $29. This also means that you’ll be able to update to Lion for half the price, as Lion’s upgrade requires a download from the App Store, which only Snow Leopard is equipped to do.
So, if you still hold a MobileMe account and you're rocking Leopard (or something older), here's the chance to get caught up half a decade of OS upgrades for cheap.