-the first Windows operating system to actually support touch
-faster startup/shutdown
-Ribbon interface in Windows Explorer
-ARM support
-full screen apps
-faster user logging in and out
-better SSD support
-improved energy efficiency
-improved visual performance
-XBOX Live integration
-potential Xbox gaming-simple and beautiful design
-pdf reader
-potential People Hub
-potential advanced biometrics to log users in
-new and more animated
-this is going out on a limb but device consolidation since people play with their phones, you can now with Windows 8
-enhanced networking
-a plus for enterprises that use tablets, now they can run one operating system
-Windows Store
-no more ipad!
-Windows Live ID login
-hybridization between a cloud and local operating system
-IE 10
-hopefully a new and pretty sounding sound scheme (no more vista for crying out loud!)
-no more design influence from vista-new Media Center when it comes out
-new DVD Maker if it comes out
-Windows update harassment is gone
-every device is friends with Windows 8
-the Windows 95 of our decade, simply the hugest change to Windows EVER
-puts relevant information first
-no more android!
-hopefully and Metro designed Media Player
-the PC literally is being recognized by Windows as a PC
-non frightening BSODs
-a lot of fun to switch between Metro and Desktop, and fun hitting the Start key
-Windows 8 shows that Microsoft is willing to intentionally risk their reputation (again) for innovation and change
And that's just based off the Developer's Preview build!