The plot can be summed up in a two minute treatment or pitch. There just isn't that much there. It's a heist movie with lots of unnecessary action scenes and a slight psychological twist. The subplot about the relationship IS interesting, but should have been fleshed out instead of pointless gunfire and chases. Not unlike the godawful "District 9" which had a great concept and backstory, then wasted it in a meaningless action flick. So disappointing.
The narrative in "Inception" just doesn't work. As pointed out, it was entirely wasted in exposition. The exposition explains what happens, however, it does not have a point. Why devote a large portion to "jumps" and other rules when they contribute nothing to the story? It seems like they're only there to set up impressive visuals, which are impressive, but give you no insight into the characters or tell you anything important? I got nothing out pf the film except that I really liked most of the visuals.
Comparing this to "Star Wars" or "Aliens" doesn't really work. Those are popcorn movies. Very well done and entertaining popcorn movies. The difference with those is that they have fully formed characters you care about. You understand them and they have lots of personality. I didn't take anything serious from them, but neither were they a pretentious bore, like "Inception." you don't have to be deep and meaningful to entertain. Just like "Avatar." I went in expecting to hate that movie. I knew how it would end shortly after it started, but Cameron spent enough time on the characters that I didn't care. Sure, it was full of clichés, but it was great entertainment. I appreciate that. "Inception" has all the pretention of a serious movie, yet fails to deliver. No characters, no great themes, no humor, no life. It's like a dead-serious soap opera that ends up telling you nothing.
This will not be a classic in any way. In ten years or so, the hype will be gone and people will recognize it for the waste of time it is, just like the leaden and dreadful "Dark Knight." I actually sat through that twice, just to make sure I didn't form an opinion on a bad day. Nolan will go down as the most successful bad director of his day - much like James Fenimore Cooper. If you haven't read Mark Twain's criticism of his literary crimes, you really should. Every point directly applies to Nolan and his work.