So which is better? "GH3" or OM-D?

I don't yet have a GH3, so cannot answer your questions, but best check the Panasonic website because they do have quite a lot of information.

Video is useful for family if not professional use. Being I am now an Uncle, I am keen to record my niece in the highest quality possible so that when viewing the footage in the future, it will still look good - unlike the grainy spidery 8mm movie film footage shot by my grandfather in the 60s and early 70s on his Super-8!

If I could afford it, would buy a 4K video camera - which would probably make for a nice stills camera too because you could grab frames from the video footage! (But that's another discussion, sorry, I'm waffling!)

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