Will someone answer Infinity Sirius' question, before everybody makes a fool out themselves?
Suppose Kermit's return was in the books at Sesame Workshop and Disney. If we started a high-profile petition, they'd likely scrap the whole plan, so it doesn't look like we're at credit. If they had a plan to revive Kermit, and continued with the plan after a petition was formed, then we'd think we were Kings of the World, and we'd think as a community that we could get them to change whatever we wanted. You're only digging his grave further, if you start the petition.
Besides, no matter how much we want anything to change, Elmo satisfies the viewers, and he satisfies the current educational goals Sesame Workshop is working towards. And in the end, 99% of Sesame Street viewership is kids, and parents who want what's best for their children. Satisfying the few thousand casual watchers on this board is far down on their list of things to do.
Kermit? Quite frankly, no matter how entertaining he may be, he just interviews fairy tale characters. To try and get him back on would be a fairy tale.
Plus, suppose they were to bring him back on, the Muppets in general would become even more associated with preschool entertainment, and the rumored new FOX Muppet Show would be an even heavier lead balloon to get off the ground.
I hate to be the bringer of bad news, but it's not going to happen.