This is what I distilled from the OED:
Innovation is the alteration of what is established by the introduction of new elements or forms; something newly introduced; a novel practice, method, etc.

I’d add that it’s a word with a positive flavour and that, to be classed as an innovation, something must endure or have a noticeable effect.

I’d say that it differs from creation because creation is to make something new, whereas innovation is to employ something in a new way, or to introduce something already created.

It’s got a techie flavour, not an arty flavour.

Who was that discourse guy who talked about the flavour of words? Was it Volosinov?