The definition of "game" is what becomes the changing point tho, because a game can be the match himself ((a game between players) or the game as a whole which includes more things, and so what is outside the game depends on your definition of "game".
http://www.google.com/search?source=dict-chrome-ex&defl=en&hl=en&q=metagame&tbo=1&tbs=dfn:1
Metagaming is a broad term usually used to define any strategy, action or method used in a game which transcends a prescribed ruleset, uses external factors to affect the game, or goes beyond the supposed limits or environment set by the game. ..