UPDATE: 4/2 - If you haven't figured it out yet, this was an April Fool's Day fake story.
Earlier today Sony/Columbia studios confirmed what a lot of sources were saying. Here's the final word from the studio...
"We've heard the from the fans that Carnage is very popular, and we really want to deliver on this one. So, after careful consideration, we've decided that Carnage is going to be the villain that takes center stage in Spiderman 4."
On if Kirsten Dunst has been contacted on returning...
"Yeah, well, a lot of people don't like her, and she's not a natural red-head anyway. It's time for Peter Parker to develop a new love interest in Gwen Stacy (Bryce Howard), so, we'll probably kill off Mary Jane in this one. We're still figuring out how to do it. We want it to be gruesome and dark. It's all about the darkness these days."
Will the Lizard get his shot at villainy in Spidey 4?
"No. The Lizard is lame. (Laughs) That's kind of a running joke at the office. We set up Dr. Connors (who becomes the Lizard) as Peter's college professor from the first movie, and now we're doing 4 & 5 and are STILL passing him by for other characters."
So, there you have it. Let the discussion begin.