Shaba Games were actually working on a sequel back in 2009 called 'Spider-Man: Classic', which was to be released around 2010. It would have allowed you to play as both Spidey and Wolverine, and the main villians were going to be both Carnage and Mysterio. Unfortunately, Shaba Games became bankrupt whilst working on this game, therefore Activision decided to shut them down.
The only chance we'd get of having a sequel to Web of Shadows or at least a remastered version of it would be if an another game company took this idea on board and had the rights to be able to do so.
Web of Shadows is still my favourtie Spider-Man game to date, but the chance of us getting anything similar to it likely won't ever happen.