Doom is a copy of Dungeons & Dragons. WoW is a copy of Everquest FFX-2 is a copy of WoW Quake is a copy of Blood Blood II is a copy of Quake II the list goes on, and on. What really matters is that it doesn't matter whether or not a game is a copy when it comes to game quality. Exept for WoW, it will always remain gay.
I hope you did not just realize this now? New game concepts are a rareity these days. Most games are just cookie cutter copies of something else. Bioshock was a copy of SS2 with a minor change of scenery for example. People copy already successful games/franchises, in hopes that by copying, they will copy the success - or franchises just continue releasing new "content" that is just the old game with a new theme (COD5, cough cough.) The number of games out there that are truly innovative is pretty low.
Some of the brighter ones are realising that there's money to be made capitalising on things other companies have done but made mistakes with. eg saints row and GTA. GTA4 isn't very GTA when compared to the other titles in the series, saints row 2 is GTA:SA with more bells and whistles and better crazy shit.
or the dune clones, OHWAIT thats a game genre now cloning is part of the thing, no cloning, no content
