The 600D looks almost identical to the 550D. It's slightly heavier and wider, so it looks more 'muscular' as a result, and has more leather accents. The layout of controls are also almost identical, but have been refined. The grooves on the back are more deeply contoured than the 550D's, especially the right-hand thumb grip which makes the camera easier to hold. Unlike the 550D, the 600D comes with a three-inch swivel LCD, and it has the same resolution as the 60D's LCD screen at 1.04 million dots, giving you stunningly vibrant previews.
In general, the 600D handles well. Controls are conveniently placed, giving you quick access to essential settings. The camera feels good in the hands, especially with the improved thumb-rest; the AF system is quick and dependable (except in Live View), and the camera responds quickly to the shutter release.
The 600D's auto-focus is slow in Live View (i.e., when contrast detection is used), usually taking three to four seconds or so to get a lock. There's no automatic follow-focus when shooting video, but you can enable a half-shutter press for re-focusing during recording. Live View AF speed improves if you switch over to Quick Mode (which enables the more traditional phase detection method), but that works by shutting down Live View for a few moments while the camera focuses, which means you won't be able to see anything until focus is achieved and Live View resumes. If you shoot primarily with the optical viewfinder, the AF system is dependably fast and accurate.
We like the dedicated ISO button on the top of the camera, which gives quick access to ISO settings. Like previous Canon EOS DSLR cameras, the Info view on the LCD becomes an interactive menu when you press the 'Q' button, giving you quick access to various settings.
Like the 60D, the 600D offers no quick, one-step way to record video. In modes other than video, the Record/Live View button only toggles between Live View and the optical viewfinder. To shoot video, you have to exclusively be in video mode, wherein the Live View button then becomes the Record button. Unlike other cameras like the Panasonic GH2, you can't quickly grab videos while in other modes.