Re: IRON MAN III (May 3, 2013) - Official Trailer Premiere
I doubt it will be an all serious affair, we saw in The Avengers how the balance of humor and epic keeps the pacing at a perfect level.
It does look to be more epic than the previous Iron Man's however. In the last 10 years or so these studios have been shown how comic book movies can be epics, and still succeed. Which is great because they are epics as far as story is concerned in the source material. I'll be very interested to see how this second Phase of Marvel movies begin to ramp up the epic side of comics, in an effort to prepare for Thanos, who will likely be the most ambitious on screen comic character when he debuts. (Because lets be honest, Galactus in FF2 doesn't count at all. What shit that was!)
I anticipate that Thor 2 and especially The Guardians will be extremely epic too.