Definitely a treat to see in the theaters but I have to admit I didn't remember large portions of this is as I thought I did (In fairness I saw it 5 years ago). I actually enjoy the first act, I know there's a decent amount of people that think it is a bit boring but I find it fascinating to add to the overall mystery of this project. The middle section is just brilliantly done sci-fi which is very enjoyable, but I will admit it does drag a couple of times. The Jupiter mission is phenomenal and may have been able to work on it's own as a short, however that is where it gets transcendent for most people. I still haven't made a conclusive decision on what it all means, and quite at this point I think Kubrick purposely made it have no meaning (but with mystery) to leave the audience searching for answers behind all of it but that's just my interpretation.