Start Button returns even if it just takes you to start page.
Complete elimination of the Prev App bar and return to app switching of Windows 7.
New nice icons throughout system.
Native ability to select custom icon for any icon in system, including library icons.
Ability to move Charm bar as you can move taskbar
Ability to turn off Charm Bar and use traditional start button to go to start page.
Option to boot directly to Desktop.
Option to "not" add icons for new app installs to Start Page.
Consistent and hiccup free scrolling in all Metro apps
Ability to change Start Page background to wallpaper or show desktop behind Start Page.
iTunes comparable app for Windows Phone/Zune/Tablet Devices - A metro app will be fine.
Better Media Player.
Native Facebook Metro App.
In-place context sensitive menus in native Metro Apps.
Native Metro Fitness app to log diet/exercise with a Windows Phone companion app with GPS recording.
More Stable USB 3.0 Drivers for NEC, and TI chipsets.
Native Thunderbold support.
More GPU-acceleration wherever applicable.
More utilization of multiple cores.
More utilization of memory for systems with 16-32GB.
Metro Geometry Wars, bundled.
Metro Lode Runner, bundled.
Metro I made a game with Z0mbies, bundled.
Purchase and play all XBLA games on Windows 8.
Full Bitlocker (TPM Support) in ALL versions of Windows 8.
Native Blu-Ray playback support (MS subsidizes license fee for codec

Bundled DivX, Xvid, and native MKV codecs/playback support.