It's lighter and faster. Performance wise, everything is better. This was already shown last year with the original 8 benchmarks. Security is better. Better search function, better task manager, refreshing/resetting windows is easier. Haven't had any issues with anything yet. There's a lot of things better. The only thing people don't like is the ui changes which is easy to learn anyways. If you have 7, I can't really say it's worth $100 to upgrade. But for a new rig then I'd say to get 8.