The thing that I *LOVED* about that video was that, even though "similar" shots were displayed over and over, there were never any "identical" shots.
At times, it's not the uniqueness of the thought behind the shot itself, but perhaps the uniqueness of "that moment". I've captured pics of places, things, people in settings that many others have, and I get comments like, "I took that same shot last year(week/month/whenever) and it never came out looking like THAT!" I guess it depends on what you consider "unique", too. For some, it's their editing "touch", for some, it's them shooting something they've never seen anybody shoot before, even though it may have already been done.
I liken it to Fantasy novels. "Oh noes! Old king slaughtered by evil, child hidden away for his own protection, but he's the rightful king, REVOLT!" or "Oppressive powerful dark force needs to be conquered by the least probable candidate!" It's all been done before, but every once in a while it's done so well it become the next best seller.
FORCE yourself to think outside the box. YES! That's good! But do it before you look on Google to see if it has "been done" before, or you're going to run out of ideas really quickly, and/or you'll lose your unique view of the world because you're more worried about duplication than you are creation.