Overall, this film runs as smoothly as any comic-book-to-film adaption I've ever seen. There is just so much fun is too be had with this film that it can't possibly be overlooked.
Although the final act doesn't really deliver the goods, the film as a whole is very fulfilling. It serves as a really fantastic origin story that has some fantastic character development as well as acting which is what truly drives this film along with Favreau's terrific direction.
I don't think a lot of people were expecting much from this film, which is why I think it is received so well. The chemistry between Downey and Paltrow is pure gold. Undoubtably the best comic-book relationship story ever told and I honestly don't think you can compare it to any other comic-book relationships because they're all pretty mediocre which is another reason why this film is so great.
Another reason why this film is great is simply Downey as Stark; best damn match-up ever... period.
I loved the way it ended off with Stark revealing he's Iron Man, the last act was cheesy but, it was nessisary for every movie like so. But, I can gladly put that out of my head because this film is terrific. Totally exceeded my expectations.
Rating: 8/10
Oh!
The after credits scene... it was... okay, I guess. Sam Jackson as Nick Fury I think was seen like miles away. I honestly wish they didn't add that in, I wish it was just left with what that guy from the "S.H.I.E.L.D" said about the shortened version of the company's name. I was surprised when he made that reference I was like:

. But anyways, it was nessisary as well I guess for any type of 'Avengers' movie to happen in the near future(which I would hope to be directed by Favreau, or others who will work on the seperate versions of the hero adaptions and sorta add in a team-effort but mainly focus on their own character's delemas, whatever).