No I'm thinking about uniqueness of this logo image. The picture was sold for a long time on this (and few others) stock image sites. It is still available there.
Should I get (buy) some exclusive rights ? If I do this — what happens to the people who bought this image before? Should I just add the unregistered trademark™ symbol somewhere near this image and site name? Should I ask the artist to modify the image to make it unique? (something like adding one or two letters from the site name, "pied piper" style, you know))