I enjoyed it. A nice teaser. It didn't reveal the entier movie, or even what the movie's about. It wasn't a 2 minute version of the movie, which is always great.
I also liked how practical most of the visual effects looked. It didn't seem to have that weird, green screen look that the prequel trilogy suffered from. I'm hoping Abrams did mostly practical shoots, with special effects being used just for that, "special" effects. That cross guard on the lightsaber is silly.
The shot of the Falcon was amazingly cool, as was the shot of the X-Wings over the water.
With all of that said, I don't think it was an incredible trailer, just a very well done one. My rule of "Better the trailer, worse the movie/Worse the trailer, better the movie," has me concerned, but the trailer was jaw-dropping. The theatrical trailer is what I'm craving next.
I'm excited for a Stars Wars movie again. Of course, I was just as excited for the prequel movies as well back then. I'm a fan of J.J. Abrams, however, and have enjoyed all of the movies of his I've seen so far.