I have watched the heck out of 2001 for a good thirty years. 2010 has always been fun, but not anything like the same tone. There are a lot of "I wish" things about the latter film. I wish they'd worked harder to have Heywood look and sound even somewhat like the same actor. I wish they'd spent more time understanding the Discovery. Much as I missed the centrifuge, too, I was more annoyed that the emergency airlock was relocated to the port centerline of the ball, that the velcro "Grip-Shoe" flooring in the pod bay was replaced by polished linoleum, that the actors didn't even try to stay on it, that they leaned on the pod and windowsill and HAL console in what was supposed to be a microgravity environment, that the parts storage room was turned into an accessway... The technical precision of the older film demanded a particular pacing and mood that wasn't much in evidence in the sequel. Between that and having sound in space, I think Hyams dropped the ball on opportunities to contrast action with stillness.
There are also more subconscious things that ping the "something's off, here" sense for me... HAL's lenses are bigger and faceplate proportions are different. It's subtle, but they look fatter. The look of the spacesuits and pods, rather than being an evolution of what we saw in 2001 are an extension of what we had in the real world of the mid-'80s. Ditto the politics, which somehow seem more dated then the politics in 2001. The proportions and finish of the monolith were off, even. And I still wish the music had more bits there were evocative of 2001 -- not necessarily all the classical stuff, but the Ligeti pieces.
Grumbling aside, there are some truly epic moments in 2010. I love the report at the beginning, and have no issue accepting the retcon of Bowman's "My God -- it's full of stars!" It's a line that still gives me chills. I love the smash-cut from Floyd looking in on his sleeping son to the Leonov. I love the actors portraying the Soviet crew. I love the bit between Bowman and his mother. I love the boarding of the Discovery, reactivating of the ship, and reawakening of HAL. I love the apparition of Bowman to Floyd and their conversation. I love the final conversation between Chandra and HAL. I love the docking of the ships and their escape from the nova. I love the last scene on the terraformed Europa. But I think that's what tends to frustrate me more about this film -- I keep being sucked in and then jarred back out. *shrug*
--Jonah