If you bought a qualifying Mac from an authorized retailer on or before the 6th/7th of June, you are eligible for a free upgrade to Mac OS Lion (10.7). Lion is available only through the Mac AppStore, so all you need to do is head over to the Apple Up-to-Date page and get a redemption code; enter this code in the AppStore and you’re good to go. The 4 gig download is quite a pain though, wish they had a boxed option for those of us with limited bandwidth. I heard you can download Lion free from an Apple Store if you happen to have one in your area… or country… or continent. I had trouble finding this so hopefully it will help someone.