The New Yorker has a history and a consideration of the plot. FilmSite calls it a masterpiece. io9 says, "One of its most enduring qualities is how open to interpretation it is—over the years, the enigmatic film has inspired some fascinating (and/or delightfully batshit crazy) theories about what it all means. This is exactly what the director intended." Slant Magazine has a positive review.
The BBC opens with this:
It’s been 50 years since the release of 2001: A Space Odyssey, and we’re still trying to make sense of it. Stanley Kubrick’s science-fiction masterpiece is regularly voted as one of the greatest films ever made: BBC Culture’s own critics’ poll of the best US cinema ranked it at number four. But 2001 is one of the most puzzling films ever made, too.Roger Ebert considers it a Great Movie and closes it by saying,
Only a few films are transcendent, and work upon our minds and imaginations like music or prayer or a vast belittling landscape. Most movies are about characters with a goal in mind, who obtain it after difficulties either comic or dramatic. “2001: A Space Odyssey'' is not about a goal but about a quest, a need.Empire Online concludes, "movies were born for experiences like this." Rotten Tomatoes has a critics rating of 92%.