If a shot that has been taken a million times before it's probably because it's an interesting/photogenic site or view. So why not add it to your collection?
It's a really great shot and you took it! Plus there are probably millions of 'normal' people that have never seen that picture and you can be the first to show it to them.
I think this issue may be more relevant to those of us that want to push the envelope and step outsdie our comfort zones. For example; capturing a portrait model in slightly different surroundings and with different lighting in a different pose should be something we can all try, rather than just defaulting to a standard acceptable composition.