I was just about to talk about this exact topic. Blizzard say one thing and do another. They said they were putting in the AH/RMAH purely as a legit and easy source of trading so players wouldn't have to go through out of game, dodgy places. Then however, after the release of the game they tell us that the AH has actually affected the game, in the most intimate possible way for Diablo, the drop rates. They tell us that because you can use the AH they assume you will, and because of that assumption they must adjust the drop rates as if you're playing in a game with a few million people rather than 1-4 players. So their very first statement they made about the AH is a lie.
I'm not sure what other people have experienced but on my Barb all the way to 60 and now my Wizard up to 42, I have yet to pick up a single usable, level appropriate weapon. Considering the effectiveness of your entire character is based on weapon dps, having a crap weapon means you character will be crap, simple as that. So to remedy that I've been forced to purchase new weapons on the AH at regular level intervals in order to progress at a steady state.
I'd talk about the poor/boring itemization but I've run out of juice. :D So maybe later.

