In a nutshell, Inception is a fantastic movie - multi-layered, thought provoking, action packed and very well acted. Miles above a lot of the dreck that has come out this summer, heck even this year. More spoilerish thoughts below...
The technology exists to allow people to entire your dreams and steal information. But Dom Cobb is tasked with something even bolder and more dangerous - breaking into someone's mind in order to plant an idea.
The trailers for Inception left me intrigued and a bit confused as to what to expect and the 2 plus hours of running time left me a bit iffy. But consider my mind blown - the movie is outstanding with a fantastic story, especially if you buy the conceit that we're actually in Cobb's dream because frankly the notion that Inception is primarily propelled to prevent a business competitor's global domination is not all that exciting.
The dream within a dream within a dream makes Inception feel like you're in different movies - at each layer, characters have different motivations. It makes you question the nature of reality though not as masterful as The Matrix did.
I only have two problems with the movie - the interaction between Mal and Cobb near the end, though needed, dragged down the story's pace and Ken Watanabe's pronuncation issues. A lot of the time I felt like he was talking with a mouth full of marbles. Still, these are minor quibbles that don't detract from the awesomeness of this movie.
I'm going to watch it again before I get into a philosophical and psychological debate about the nature of dreams and reality.