Fears that Pluto's atmosphere may freeze and precipitate onto the ground before New Horizons gets there seem to be overblown. The article also seems to imply that, while Pluto isn't really a planet in the way the eight in our solar system are, it's not really an overblown comet nucleus, either. I guess what it is will have to wait for the fly-by, and various new grants that data will need for proper analysis.