One of the big questions that I get is “Should I get a digital still camera with video function or a video camera with still function?” My answer has always been the same, if you want to get good video get a video camera, if you want to get good stills get a digital still camera. I know that manufactures have come up with some major advancements in the capabilities of each type of camera (video cameras that will take stills and still cameras that will do video) but at the best it is a trade off in features and ease of operation of each camera and at worst you are loosing many valuable features that will assist you in getting great pictures or video.
Now I am not saying that if you are on vacation and you see a great scene and all you have is your video camera that you should not take a few still pictures. But if you are looking at doing a lot of either video or still then you should get a camera that will do that. Seeing the bouncing of a video that was shot with a still camera that does not have the ease of controls of a video camera is very common. As well having people bring in a still image that is out of focus and over exposed shot from a video camera is also common.
What I tell people is decide what you want to capture mostly if it is video then spend your money on a good video camera. If it is stills then spend your money on a good still camera that you can add on features such as extra lenses or flashes.
One extra thing, I recently saw a Canon 5D with a video viewfinder that allowed the operator to hold much more like a video camera. This helps to reduce a lot of the problems inherent with the dual use. Only problem I see here is that it is costing you $4000.00 to be able to do this, if you bought a good video and a good still camera you would be at half of this price and have twice the capabilities.