Ever since the Reign of Gunthers, I've been trying to understand who Jay T. Doggzone really is.  I strongly believe Jake is Jay T. Doggzone.  My first clue is that Jake has been known to be a writer, writing a newspaper article that he has never featured the Red Squirell in.  My second clue is his name.  I think Jay T. Doggzone could be the pen name for Jake The Dog, since it has the same initials and is only slightly different from Jake's full name.  Jake also tells Finn not to read it, probably because he doesn't want Finn to find out he wrote it, or he's embarassed by the fact that he wrote it, or possibly thinks his own advice is bad.  Also, in All The Little People, several pages have the word bu-bumps, which Jake used many times in the beginning of the episode.  Those are my only clues so far, If you have a different theory or more clues as to Jay's true identity, please let me know.  Thanks for reading!