Eventually, 'Castle' will go off the air (hopefully not for awhile) and I'll be able to invoke the 'Primeval' temporal reboot to the show in order to bring it back into the main Toobworld. With the reboot, Richard Castle will no longer be friends with the Mayor of New York City, who happens to be a black man named Bill. Instead, he'll be friends with Mayor Mike Bloomberg, who is the mayor concurrent with the series and who has appeared as his own televersion in shows like '30 Rock' and 'Law & Order'.
I had toyed with the idea that maybe 'Castle' could reside in the dimension for 'The West Wing', as I don't remember hearing any mention of Presidents Bush and Obama, or any of the recent Presidents in the established timeline for the main Toobworld. (In 'The West Wing', Richard Nixon and Gerald Ford were followed by D. Wire Newman, Owen Lassiter, Jed Bartlet, Glenallen Walken, Jed Bartlet, and Matthew Sanchez.)
But that idea was dashed with the latest 'Castle' episode, "Poof! You're Dead". In it, Castle mentioned the Fortress of Solitude, Superman's headquarters in the Arctic, as well as Superman's alter-ego:
Richard Castle:
Are you kidding me?
He has an identical twin who wears glasses!
That's the worst disguise since Clark Kent and you believe him??
In 'The West Wing', Superman has yet to reveal himself as that dimension also houses 'Smallville'. And it's way too early in his timeline for the world to know that he is Clark Kent.
But in Earth Prime-Time, Superman died back in the early 1960's and his secret identity was eventually discovered. (As well as his Fortress of Solitude.)
Another reason to get 'Castle' into the main Toobworld - Detective Kate Beckett mentioned Professor X of the Marvel Comics group "The X-Men":
Detective Beckett:
With any luck Professor X will turn out to be Zalman's mystery client.
Charles Xavier already exists in comic books, movies, and the Tooniverse. It would be quite a catch if we could get him into Toobworld as well!
BCnU!