This meme has blown up recently and has been featured on multiple mainstream publications:

http://www.mirror.co.uk/sport/row-zed/very-best-randy-orton-rko-4440574
http://www.foxsports.com/buzzer/story/randy-orton-from-out-of-nowhere-vines-101414
http://deadspin.com/randy-orton-is-rkoing-the-entire-internet-1646153782
http://www.philly.com/philly/blogs/the-squared-circle/Randy-Orton-RKOs-the-Internet-and-everyone-in-it.html

A small compilation:



The RKO is the finishing move of Randy Orton, one of the most popular wrestlers of the last decade.  He actually appropriated the finisher from WCW superstar Diamond Dallas Page, who had christened it the "Diamond Cutter" in the 1990s.  However, it is believed that the originator of the move is Johnny Ace, who is a WWE agent, former WWE executive and wrestler, and the brother of Road Warrior Animal.  Ace called his move the "Ace Crusher," and many wrestlers (including Randy Orton, DDP, and Stone Cold Steve Austin) have used a variant of the move as their finishers.  Here is a video comparing the different kinds of "crushers"/"cutters":



The "RKO Out of Nowhere" meme has actually been present in wrestling forums since at least the late 2000s, but thanks to Vine it has become even more accessible to the public.

that video's great I shared it on ello

That third one in the video is pretty good.