Well to what started this thread... Right now the crew is in Kanto doing the battle frontier.  Not gym challenge.  So he probably wont meet up with any gym leaders except maybe Misty.  However, he has runthroughs with the character from Pokemon Ranger, and that leads some people to believe that there will be a filler region until theDiamond and Pearl are released, and that this filler region *might* have to do with Pokemon Ranger.  After all, the Kanto season is (or at least should be) near completion in Japan, so unless Japan either puts the show on hiatus until its release this fall, or begins the new region before the game is released (which i would prefer) then there is a huge question as to where the crew will be in Japanese episodes from probably August until November... which is about 12 episodes where they have no where to be and no goal.  Unless those episodes are spent on them traveling to the next region?

Anyway Johto is done.  Im pretty sure about that.  And I think the only reason they went back to Kanto is like syntemental value, seeing as that was the first region and the remakes of the original were in that region.