Saw this just a few hours ago. I wasn't sure what to expect, I had some general ideas and it really seemed like my kinda movie.
Unfortunately, I was very disappointed. The whole thing seemed to be geared towards pushing the actor's performances... almost like they were trying too hard to make these Oscar-worthy performance (especially Keaton and Norton). Those performances just fell flat for me, it all seemed too forced and I never really felt the tension the movie needed to work. The soundtrack (the drums) got old quick and the camera working and camera blocking (?) or set up was also jarring (I don't think you're supposed to notice that actors are standing or sitting certain way to let the camera move through).
The best parts of this one were the lead female roles (Emma Stone especially) and Zach Galifianakis was solid, too. But, even they couldn't save this... I don't get all the buzz it's getting, the movie failed on too many levels on what could've been an interesting premise.