I thought the original Spider-Man was decent, though it didn't really impress me. I really liked Spider-Man 2, and the 3rd movie was pretty good too. It wasn't as good as the 2nd one, IMHO, but I thought the ending was awesome. I'm not sure how well Spider-Man 4 would do. If the original staff and cast returned, the movie might have a chance, but otherwise, it might easily become a disappointing sequel. Sam Raimi already spent over $250 million on Spider-Man 3, so I'm not sure if he wants to make another high-budget Spidey film any time soon.