Unlike the thread linked above, it actually is only mildly spoilery; I don't think it'll ruin the movie for you unless you are practicing a total information blackout. However, I'm NOT going to screen for spoilers in the comments.
I finally saw this, so I can say things. Most of the things I’d say have been said above, though.
“The Force Awakens” was a far better movie, as a movie, than the prequels. Yet, at the same time, some things about it actually had me missing the prequels a little bit. The prequels had flat characters and bad dialogue, got bogged down in political backstory, and two of the three were 80% inconsequential filler… but they were actually visually imaginative, taking us to all sorts of environments we hadn’t seen in Star Wars before, if ever. The much-maligned “Attack of the Clones”, in particular: that movie jumps all over the galaxy and every place is beautiful in a different and surprising way. What they lacked was that Ralph McQuarrie look that people associated with Star Wars; they were more blobby and Art Nouveau. Still, it was new.
This one is the opposite. It’s got endearing characters played by promising young actors, wonderful return appearances by old favorites, a story that clips right along, some of the best dialogue written for a Star Wars movie… and a world that feels like leftovers. Everything in it is a loving tribute to some scene in the original Star Wars trilogy. Even the planets feel like retreads, even though they’re previously unseen planets.
I understand why J. J. Abrams (and Disney) did this. Abrams was effectively kickstarting the beloved Star Wars franchise for a fresh start after what was generally regarded as an ill-advised detour, and the first thing he had to do was convince people that he got what they loved about the original trilogy and wasn’t going to screw it up. So he took no chances, and made a movie that was basically an extended tribute to classic Star Wars.
But Episode VIII had better start to move on into some new territory, or it’s going to seem stale.
That said: the movie did a good thing. I have a daughter who is almost exactly the same age I was when I saw "Star Wars" in 1977. If this movie were nothing more than a shot-for-shot remake of that one with a girl hero (as people have, with some exaggeration, accused it of being), it'd still be worth it for that.