I've debated this quite a bit. Although I went to KI several times growing up, I didn't take my kids for the first (and so far only) time until 2007. WHY did we pick KI as our mini-vacation spot? Spongebob! And Dora and Scooby! (Except Blue, the other Nick characters we could do without.) So yeah, not having them there makes KI less attractive. Nothing wrong with Snoopy, but Cedar Point is just a day trip for us while KI requires an overnighter.
That said, we WILL be returning to KI for a second time in 2010. One major factor is my kids enjoyed the adjacent waterpark that is included in admission. Hope that stays the same. I'm also hoping Scooby will stick around - I've been trying to follow along but I'm confused about Scooby's licensing.
In 2011 we're planning to hit Univesal Orlando where we'll see Spongebob and Scooby. That takes some of the sting away.