600d vs 650d video.
I agree with Bjorn.
DSLRs are not suitable for casual hand held video because the viewfinder blacks out in video mode and without a steadycam type rig it is just aboeu impossible to hold the camera staedy when using the LCD for composition.
DSLRs are very good for professional type video using a tripod and an assistant to help with manual focusing. If you want a camera for casual video either get a camcorder or one of the cameras with an electronic viewfinder (EVF) mentioned by Bjorn.