I saw Spider-Man 3 this weekend and it probably counts as the worst movie in what has been a pretty good series. The action scenes were good especially the climactic battle but the plot and story in-between the fight scenes was almost non-existent. There were a number of scenes that were so cheesy I felt embarrassed for the actors. The most accurate review of the movie I saw was Richard Roeper's review in the Chicago Sun Times where he wrote

If you walked out of the exhilarating triumph that was “Spider-Man 2” and immediately started counting the days until the release of Spidey Trois, there’s probably nothing I can say that will dissuade you from racing to the multiplex for the eagerly anticipated third installment — but I gotta try, anyway, so here goes.

Kirsten Dunst sings in this movie, more than once.

At one point Peter Parker undergoes a personality and style makeover that makes him look and act like he’s the unknown third brother from “A Night at the Roxbury.”
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and a slimy creepy crawler has emerged from the space rock and is now residing in Peter’s apartment. The creepy crawler affixes itself to Peter’s face one night and enters his being, turning him into a darker, more aggressive personality who favors an all-black costume as Spidey — and a whole new ’tude as Peter.

This leads to one of the most bizarre montages in superhero movie history, with Peter changing his hair, buying a European suit and strutting down Manhattan like some clueless, low-rent gigolo, pointing and winking at women who look at him with disgust. On the outs with Mary Jane because he’s been insensitive to her career setbacks, Peter goes on a date with Gwen (Bryce Dallas Howard), one of Spider-Man’s many rescue cases. They show up at the jazz club where Mary Jane works as a singing waitress, and within seconds, Peter is banging away at the piano and dancing all over the joint like Jim Carrey in “The Mask.” It’s very goofy.

The Night at the Roxbury inspired scenes were so bad that a couple of folks walked out of the movie. Unfortunately, for them the final battle made up for the cheesiness we were forced to sit through earlier in the movie.