As we posted yesterday, Apple has finally released OS X 10.7 Lion and Lion Server.
Before you do anything else, make sure you have a backup of your Mac; Time Machine is good, and adding a bootable clone is even better. You may have no problems at all with your upgrade, but far better to be safe than sorry.
Head on over to the Mac App Store to pick up your $29 upgrade now. The download is pretty large so be prepared to spend some time watching the download ticker. Furthermore you need to be prepared that the upgrade process also takes a while. Grab OS X Lion from the Mac App Store here and Lion Server here. If you don’t have broadband access, you can download Lion at Apple retail stores.