New Features Included : App Stores, Launch Pad, Full Screen Apps, Mission control, Multi touch gestures, Auto Save, Resume, Auto hiding Scroll bars, Air drop, Integrated Lion Server, File Vault, Mail 5, Profile Manager, Folder Merging, Recovery Partition and more.
System Requirement : OS X Lion will only run on processors with 64-bit support which include any Macs with an Intel Core 2 Duo or higher.