It's funny, but I have noticed more people respecting left-lane passing rules in the past few years, at least in the New York metro area.
Do you mean the slower car pulling over into the right lane? In NY? Well, yeah, maybe, just maybe when there's an H1 Hummer with 28 "off road" lights all ablaze following 8 inches behind their rear bumper! Those of us who drive saner vehicles don't usually get that sort of response from the slow drivers. (Unless we follow right behind the Hummer.....)