I went to see this with my wife and I think I actually liked it a bit more than she did.
It has some unnecessary comic relief because there was plenty of good darker humor, but Blake Lively is really good and Anna Kendrick steals the show. Highly entertaining film, would recommend. You can see some of the twists coming, because they are basically telegraphed, but it didn't hurt my enjoyment much. Not sure why this director did the Ghostbusters abomination, because he is very good here.
Yeah, I know, right? It's not a comicbook movie with people wearing silly costumes, so it probably won't get much traffic here. But I liked it and I almost forgot about the music, it was actually pretty good, fit the film quite well.