As basically everyone has stated before, this is a completely pointless remake of a film that really never called for one. Even if Van Sant had the technical ability to make this a worthy movie (which he didn't, and probably still doesn't), there are still a ton of things working against him. One has to wonder why he even picked up the project at all.
The most poisonous problem is, obviously, the legacy of the original directly working against it. There's an odd thing I truly don't understand about remakes - when shit like Transformers gets picked up, everyone gets all excited and nostalgic about it. TMNT too but God help you if you liked that movie. Horror remakes, however, are almost universally reviled. I won't postulate on this because I honestly don't know why this is so, but it's interesting to view Van Sant's attempt at avoiding it. Quite simply, he films a shot-for-shot remake with some incredibly slight differences. As if terrified of disappointing the film's following, he packs a bunch of big names into what are effectively 10-minute roles and has them include extra flair so as not to be forgettable. Psycho reeks of trepidation, which dooms any movie from the start. And when it does make changes, they're usually for the worse. The infamous shower stabbing, for instance, is made far more violent, splashing the scene with extra blood and crunchy sound effects. An inevitable treatment for the late 90s. Also bizarre is watching Norman Bates...well, masturbate while watching hapless Marion through his little peep-hole. Another slightly amusing change is the removal of any mentions of transvestitism from the ending monologue. Psychology has really changed in 40 years, huh?
But even though it does preserve the screenplay and cinematography of the original, Van Sant fails on several levels. The performances he commands were doomed to be lost from the beginning. The actors delivering these lines find varying degrees of success, but all of them are uniformly overshadowed by the roles of the past. The worst is Anne Heche. She is predominantly bad, bringing this bizarre half-pixie, half-bitch quality to a Marion Crane that simply didn't call for it. Her miscasting is fatal; she is too goofy and airy for this role. She does have some okay scenes (she is interesting, if not obvious, during the dinner scene) but ultimately I actually found myself kind of glad that she died. Julianne Moore, as her sister, is the most modernized of the characters, attempting to bring a personality to the unmemorable Lila Crane. It comes off as a bit overexaggerated. William H. Macy is decent, as is a surprising Vince Vaughn. Sure, he'll never live up to Anthony Perkins, but he plays an interesting Bates. I also feel like a bad person for finding him incredibly hot. Whaaat?
Psycho's step into color is the most obvious change here, but it doesn't really enhance or augment the movie in any way. I could wax philosophical on how black and white movies are more meaningful because they make the images more vivid, but that would be pointless - a black and white movie in this day and age is generally financial suicide. Still, this movie was DOA no matter what Van Sant did to help it out. It's an interesting study on performances at the very least, but overall not worth the time.