I watched Iron Man last night with my sister, my dad, and my cousin. I was able to point out all the awesome stuff and early bits of broader Marvel continuity to them, although my dad had already seen this movie before. My dad went nuts over Jim Cramer's cameo and at Obaidah Stane's "TONY STARK WAS ABLE TO BUILD THIS IN A CAVE! WITH A BOX OF SCRAPS!!!", as did I. :P
I also think it's interesting and surreal to think that this movie is part of the same universe as the Thor and Captain America movies. They just have such different feels to them...
I can see why it receives such high praise. I was astonished to find out that Al Pacino plays Michael Corleone. I understand that the film's over thirty years old, but he's unrecognizable even remotely. Anyway, I can't wait to watch the other two.