I went to see Spiderman 3 yesterday in the theater, and I was also disappointed with the film. It definitely felt like they tried to cram too much into the movie, some parts were very cheesy and some parts were slow and just plain sucked.
The butchering of the original storylines was also disappointing. Everything has been skewed and butchered from the original comic book story lines. For one, just as Morpheus said, I was also wondering when the symbiote suit would start transforming into regular clothes, but it never happened! Unbelievable!
I really hope they do better with Spidey 4 and beyond. So far, my favorite is probably Spiderman 2. This is probably due to a few reasons, but mainly because I like the villain Doc Oc way more than the goblin.
For the sequels, I would like to see Scorpion, The Lizard or Kraven, but NOT 3 villains in one movie. 2 at the MOST, with proper character and plot development (and sticking closer to the original story lines!) ...