I have heard from some unconfirmed but reliable sources that Moose and Zee will be leaving Nickelodeon to make way for a new campaign for the channel. The new campaign was compared to a AT&T campaign where there are a lot of colors and things. I believe it would be something similar to the Rethink Possible type of commercials we have seen in the past.
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What I also heard was that Nickelodeon was really going to focus on Dora The Explorer as part of this campaign as it is the biggest money maker that they have. What this means is that Dora should be the focal point where all the other characters from the network will kind of circle around her. I love Moose and Zee and all three of my children have grown up with them, but they do seem a little long in the tooth without any new material. Plus when you think of Nickelodeon they are not the first character that I think of so why should they be the mascots of the station? Dora is the first character that I think of when we start talking about kids shows on that network. Like I said all of this is rumor at this point, but stay tuned if we hear any confirmation from these sources. Maybe Nickelodeon can confirm.