No Dan you have it right...
I go to take a portrait. I set the rebel ti the "portrait" setting (wont/don't, have 7d)...
Press shutter release and the camera fires three images. two of the images catch subject mid-blink ...
As with many such judgements it would depend on the exact situation of each case.
1. In the exact above example they would probably be deemed different images. Look at the camera/look away from the camera - you have a totally different interaction/emotion. Change the smile on the Mona Lisa's face and most art critics would say you have a totally different image. Of course in your specific example would you really have any use for an image of someone blinking - wouldn't that go straight in the trash?
2. If you shot three images and all were the same (no blinking) then, as per my first post, the law would deem them to be the same image for copyright purposes. Plus, regardless of the law, someone with an exclusive right to the image would almost certainly deem an attempt to sell the other copies as an act of bad faith and want to take appropriate action.
3. You get one great shot and two funny out-take shots because the subject sneezes or something. The out-takes would be considered different and thus separate for the purpose of copyright.

