So, it occurred to me that for all my nerd talk, I'd never seen that movie. I've been getting a lot of movies from the library lately, so I put in a request for it and got it a few days later. I finished it last night.
I took a film class a couple of years ago. We talked about 2001: ASO a lot. It was filmed on 70mm (technically 65mm) film stock, it had ground-breaking special effects, it was full of symbolism (much like Citizen Kane), it went vastly overbudget and was either hated or loved by the viewers.
I have to admit, I didn't quite get it while I watched it. If I'd watched it a couple more times, I think I would have figured it out, but instead I cheated and basically had it explained[1] to me.
If you haven't seen the movie, you may not want to follow that link. Then again, maybe knowing the meaning beforehand will help you pay attention to the movie. It felt like an art film with a huge budget, which means a lot of stuff happens that is symbolic or has hidden meanings. Things I just didn't understand at first, but could appreciate afterwards.
All in all, I really liked it, but it's one of those movies I'm not going to recommend. If you think you can handle 2 and a half hours of sci-fi art film, then knock yourself out.