No Spoilers Here! Don't Worry!
Inception was everything I could've hoped for (and more!) in a big, action-packed, summer blockbuster. There was a lot of "sitting at the edge of your seat" tension; loud sounds; sensory overload; cool but outrageous sets & computer-generated set models; action-filled fight scenes; car chases - basically, everything you would expect.
In addition, though, you have a really cool plot concept. Not spoiling anything, the plot is about a guy who's hired to tap into people's dreams. The theory being that when you're dreaming, your subconscious is flowing freely, so the guy is able to come into the dream and extract the desired information. That's cool. And original. And a lot of thought was paid to coming up with little details about this (for example, if you're in someone else's dream and you start to do weird stuff that might make the dreamer question the reality [allowing him to rationally understand that he's in a dream], all the people in the dream start to look at the person doing weird stuff, since they are all projections of the dreamer's subconscious). Cool stuff.
And the setup of the movie is cool in that there's a sort of ethereal, dreamlike quality to the whole thing. The first scene opens and you have no idea what's going on or where you are - sort of the same as when you first start dreaming & have no idea how you got to where you are. But then some stuff is explained, which is what I liked most, because as the watcher of the movie, you start to understand what's going on. I think the problem with some of the big summer action movies (the Borne series, Mission Impossible, etc.) is that sometimes you don't know what's really going on until the end, which is fine, and adds some complexity. But with this one, there's inherent complexity in the idea itself, so the plot doesn't need to try to "trick" the viewer, because dreams and the subconscious are tricky enough.
I personally love to dream (which I don't do as often as I'd like) and I love to then wake up and think about everything that was in the dream. So the movie just sort of resonated with me because of that; that is, to think that what's going on in the dream could actually influence something in the "real world."
The acting was good, too. I thought the characters were well cast. And Leonardo DiCap - he's just a cool guy and a great actor. I definitely recommend overall. It's the perfect way to kill the summer heat for a couple hours.