Reviews I've read don't contain any real spoilers. Sounds like Abrams tried very hard to mirror the original films, but there's enough that's new in the film to make it fun for everyone.
I think I'm most excited about seeing Adam Driver's character. Really smart casting on that one. Maybe this is just me being sexist, but I thought he was the most compelling actor, by far, in Girls.
Also I like that both of the main guys from Ex Machina made it into the film. Just a shame they didn't find a role for Alicia Vikander.