As others have said, depends on the game.
I might be annoyed if I pay full price for a game that turns out to be short though... For example I don't think Mirror's Edge is worth £35, but I wouldn't have had an issue at the normal budget price of £20 (I got it for £3.50 in a Steam sale though so I definately have no complaints)
I think some games can drag on too long too, but that of course depends on the game.







