You’re going to notice a few differences between “Adventure Time”, the Nickelodeon short, and Adventure Time, the Cartoon Network series, when the latter premieres late next year. One of those differences will be in the background style. Pen and the show’s creative director, Pat McHale, have asked art director Nick Jennings to come up with a couple of different takes based on a wide array of art and artists – from Arthur Rackham to George Herriman to Jeff Smith – that float their boats. Nick’s been busy churning out a variety of looks. While things are far from set in stone, here are two early samples which folks seem to like real well. What do you think?