Marvel Studios scores in its first shot.

Rating: 10/10 (1 May 2008)

It'll take another viewing to confirm, but we may possibly have reached Nerdvana with this movie (incidentally, we got a trailer for The Dark Knight, but it was the teaser they initially released; meh; also, there was the Incredible Hulk teaser, which people seemed to like). I got into comics through the animated adaptations of things like Spider-Man and X-Men, so I only knew of Iron Man from his appearances in the 90s Spidey cartoon for a while. Recently, though, you can't throw a rock in the Marvel Universe without hitting Tony Stark, and I've been following the excellent current run by Charles and Daniel Knauf, as well as his appearances in other titles like Captain America, and reading the collected editions of his classic stories.
Looking only at the plot, this is a pretty standard origin film; we get the modern version of Tony's beginnings as detailed by Warren Ellis in "Extremis" (with Afghanistan instead of Vietnam), and Pepper Potts is Tony's Girl Friday, though otherwise this is strongly influenced by the Layton/Michelinie period, particularly the presence of James Rhodes as the lead male supporting character, the main villain, Obadiah Stane (he doesn't last enough to be christened the Iron Monger formally, though he uses the term in conversation earlier), and Tony's immediate motivation for becoming a superhero, which is modelled heavily on "Armour Wars". But it's the execution, the details, and, yes, the Downey Jr., that make all the difference. Robert Downey Jr. owns all, no doubt; he's utterly fantastic as Tony Stark. Jeff Bridges is very strong as Stane; he's up there with McKellen and Defoe as realizing the best film villains of the current revival. At first I was a bit put off by Terrence Howard's voice as Rhodey (softer than I had imagined; in my head he's always been more of a Dorn/Haysbert type), but he's good; Paltrow does a good job too.
The film is peppered with setup for future stuff: SHIELD (and, if you stay after the credits, ole Nick himself, talking about his "Avenger Initiative"), an expansive terrorist network referred to as the "Ten Rings" (of the Mandarin), and, my favourite, Rhodey vowing "next time, baby" on seeing a silver-grey suit of Iron Man armour.
Mild criticism might be that the final defeat of the Iron Monger is vague and not especially climactic, but it suits the purpose well enough, and the preceding fight between the two armoured knights is awesome.
10/10.