New graphics update improves rMBP scrolling performance
A graphics update for all Mac notebooks released in June 2012 can now be downloaded.
This update includes graphics performance and reliability enhancements and improves compatibility with some USB devices.
This update is recommended for all Mac notebooks introduced in June 2012.
I've done a comparison video of scrolling with a 15" rMBP on The Verge using Safari and a FPS monitor and there's clearly a big improvement in performance: