WordPress 3.3 “Sonny” Features :

New tooltips
Drag and drop uploader
Hover menus for navigation
Flyout Menus
Query 1.7.1 and jQuery UI 1.8.16
Improved toolbar
Tumblr importer
Improved editing
Improved help tabs
Improved support for iPad and other tablets
New editor API
New jQuery version
Improved performance for permalink structure with category as slug