The acting is very good, as usual when working with Hitchcock's skilled direction. John Dall is absolutely spellbinding as one of cinema's scariest villains, an intellectual whose disregard for human emotions and morals verges more on fascism than the sub-Nietschze philosophy he proclaims. James Stewart is also superb as the voice of reason throughout the tension. The rest of the cast is good if occasionally awkward in delivery, but both Dall and Stewart turn in phenomenal performances.
Another interesting aspect of the film is the homoerotic subtext. I'm surprised it made it past the censors of the day, but to modern viewers its obvious there's something more to Dall and Farley Granger's relationship than just roommates. "Rope" is an absolutely fascinating film from the master of suspense, and even if its not his masterpiece, this is probably my personal favorite of Hitchcock's next to "Vertigo".