Here's the bit i never understood with this 'growth hacker' meme: if you're working on or for an early stage startup then everyone is a 'growth hacker', right? if your people aren't working to grow your product/service/community then what the hell are they doing?

To the self-proclaimed and aggrandized 'growth hackers' - the OP is right: You're a marketer who took (and absorbed) a stats class. Stop being so fucking pretentious. Joining facebook (or whatever) after the inflection point and claiming responsibility for its growth is like joining apple four years ago and claiming responsibility for tripling the share price.