Advertising Age, a magazine containing market analysis, information and data on advertising has recently affirmed that the hype behind the gamin titles decide the laurels of the titles. The magazine says the in-game and other out-door marketing brings success to the games; i.e. more the money invested on the advertising the more efficient will be the dispersion of the games in the horde.

Giving the examples of titles like Legend of Zelda: twilight Princess and Assassin's Creed are the titles that are the hottest selling titles presently and advertising plays a vital role in making these titles prosperous.
Advertising may or may not deceptive; since the ads are planned by the game developers and he can add few counterfeits as well to the game to just give a top hype to the game. And at present the gamers are not too dim-witted that they would accept what the games developers are serving them. Fro that ESRB like non-profit originations are backing gamers around the globe. So to hold advertising thingy responsible completely for dispersion of game in the mass would be surely a big folly.
Via: joystiq