What I really dislike about it is that it forces upgrades on "educational material" that was always sufficient before like the Blue's Clues Planet song
Some good things about it:
It shows human scientists are not infallible. They can be wrong. Things we "know" can change. That's just something kids need to be ready to accept. Adults can be wrong, even highly credited adults. There is nothing wrong with questioning long standing ideas. It keeps science from becoming dogma.
It allows for some discussion, helps kids become aware of other planetary bodies because we can't erase Pluto from the dictionary, not without throwing out a lot of good old books and educational entertainment. Now we don't just get to memorize the planets. We have to actually think about what a planet is and we get to learn about Dwarf Planets, the Kuiper Belt, maybe even the Oort Cloud. After all, what truly makes space exciting, what makes it the Final Frontier, if you will (Ocean floor still gives it a run for its money on that, in my opinion, but I digress), is the aspect of the unknown, that anything could be out there. If you want a planet completely devoted to sentient cats, you can have it.
So I may be having a hard time bringing myself to create a foam sphere model of the solar system because I'd have to leave out little Pluto or include God knows how many extra asteroids, but the opportunities for learning are only expanding.