Re: IM3 a "continuation" of the previous movies good idea or horrible?
I guess as a Iron man fan I would want IM3 to be about Iron Man universe, and continue the story of Tony Stark and his friends and enemies. I do agree it seems Marvel used Iron Man 2 as a Avengers set up and not completely about Iron Man. Yes, Black widow and Nick Fury really did not need to be in the film, but Iron Man suffers from being the only franchise Marvel has right now to set up the rest of their films, so Iron Man gets pushed aside to set up Marvels other films, and is the only one audiences have went to see, while Hulk was good it essentially floped at the box office.
Now IM3 comes out after Avengers and should be about Iron man alone, but that said, Marvel seems not to really care about the character if it means pushing Captain America, Thor and Avengers.
Essentially IM3 will be the end of the franchise, while i think they can get maybe 5 films, its best to end it at 3, even though IM2 was a Avengers commercial. So, as a fan it needs to pay off the franchise, while Mandarin is not a must, there are other villains I would love to see, Madam Masque, Ghost, Titanium Man, Crimson Dynamo, Controller, Spymaster, etc, Mandarin is the most likely end all. So time will tell what happens there, but I hope it will be a Iron man exclusive movie, so far Marvel is batting .500 when it comes the Iron Man films, the first one was 100% his film, the second can be said it was not exclusively his story.