• New Maps application with turn by turn directions, traffic reports and flyover aerial view
• A better Siri
  • Sports, movies and restaurant integration
  • Ability to post to Facebook and Twitter
  • Application launching
  • Eyes Free for voice control features while driving
• Facebook Integration: similar to previous Twitter integration but better with added contact and calendar integration
• Passbook: a ticketing/coupon application to consolidate all items in one location (with time and location integration)
• Better photo sharing
• Improved Safari: tab syncing to the cloud and other iDevices and offline reading capability
• Facetime over cellular
• Coming in the fall to the iPhone 3GS/4/4S, iPod touch 4th generation, iPad 2 & the new iPad

Read more about iOS 6 at Apple.com