In Canon-land, the 7D is currently the best APS-C body for bird photography, and for beginner's budget OEM lenses, you will hear the endless debate about 1. 100-400mm f/4.5-5.6L with image stabilization versus 2. 400mm f/5.6L without image stabilization. I shoot with the 60D (slower frame rate at 5 vs 7D's 8 fps) and the 400mm f/5.6L. It took me a while to learn how to locate bird quickly, pan smoothly with the center AF point smack on the bird's head, and engage shutter smoothly. Once learned, the combo is a breeze to hand-hold all day at 2 kg total (1.25 kg lens, 0.75 kg camera body). I don't know much about adjusting AF parameters - the 60D doesn't have any, other than the mode choice between AI servo (for birds) and one-shot. The 7D is cheap now, so if you can afford a few hundred dollars more, get the 7D rather than the 60D. Skip the 70D for stills, but consider it for video. For Canon, Nikon, and Sony, Tamron just released a 150-600mm f/4.5-6.3 with stabilization that may be very good optically - reports are not yet commenting on the AF speed, the lens has been released for Canon only for a week or so.