It's been awhile since Sam Raimi spoke up about Spider-Man 4, back when Raimi didn't want to confirm that Dylan Baker as Lizard would be the next villain to fight Spidey. Now MTV reports Raimi told Empire Magazine: "I like it in the Marvel comics when Spider-Man fights Morbius. He's really cool. A vampire! I like that combination of superhero plus supernatural."
Morbius the Vampire instead of the Lizard? Considering Raimi's horror roots, and some Spider-Man comic book history -- a 1971 issue of Amazing Spider-Man had the Lizard and Spidey team up against Morbius -- and Morbius seems like a very plausible choice.