In an interview with iFMagazine, Jon Favreau (finally, the actual director for the long-in-limbo Iron Man movie) made some statements that will make longtime fans of the character very happy.
A few select quotes:
"Of course you want to keep all of the complexities of the character; to me it's a very appealing character. Later on the books even dealt with alcoholism, but I think certainly the complexity of the character is about a guy whose life is always hanging in the balance due to an injury. There are the relationships that he has with women, with the government, and with supporting characters."
Sounds like he may be downplaying, or even leaving out the "Tony Stark as alcoholic" angle. I'm actually really fine with that as that's a plot point that could conceivable define/dominate the character, and that's not what should define Tony Stark.