Even if it were perfect, people would still complain. That just seems to be the attitude of the population at large any more. They have this sense of entitlement and when things aren't just how they want them, they go off on a tirade and make themselves out to look like idiots.
Constructive criticism and portraying that to the game devs is perfectly understandable, but unfortunately, most people who complain don't even know how to use proper grammar let alone get their opinions across without yelling and screaming through their keyboard.
Crysis 2 definitely has its problems, but damned if I'm not having a blast with it. I'm completely hooked on Crash Site.