In reply to 01wills:
All DSlrs will capture a fast moving shot as long as you set your shutter speed fast enough. I believe in most if not all cases any image stabilisition is built into the lens not the camera so if you are concerned about image stabilisation then invest in good quality lenses (hmm 70-200 f4 IS L for me for christmas
). I have tried taking a few of the Red Arrows on display and motor racing and it's basically down to technique. Set a good fast shutter speed using the Tv mode, you might want to experiment with the shutter speed if you want to get some blur in the background that sort of thing but basically I find if I pick the point I want my exposure and then track the target inbound, make sure the camera is set to burst mode and just snap away. Make sure you set the AutoFocus to Servo mode so it will continually focus.
The better DSLr you get, the faster the burst shot is going to work (EOS400D can take 10 shots @ 3fps in RAW format iirc).
Oh and iirc shooting action goes through batteries like mad