I've always been curious as to whether the whole reading people thing was exaggerated for the tourists. I'm sure poker strategy is a lot about trying to gauge what an opponent is doing, but does it really come down to people scratching their noses funny?
I used to play soccer quite a lot, and playing well is a lot about knowing whether both your players and their players are going to go. The thing is though that it has nothing to do with explicit tells - its all about the geometry, the state of the game and how they are playing.
I've always though past a certain level there would just be no way a poker player was going to reliably give themselves away.
Reading people is what poker is all about, but tells (mannerisms) are overly emphasized to a large degree in the media. They really aren't much a of a factor once you move beyond total amateurs, though at the same time, a relatively large % of the players you run into at the WSOP main event are playing their first live tournament anymore.
Really, though, it's more about observing how your opponent plays (both long term and short) and putting him on a range of holdings.
