According to #!@%*#.com, this movie has the distinction of being the biggest financial failure in the history of Walt Disney Pictures, and I guess it heralded the beginning of the end for traditional hand-drawn animation. I never saw it when it first came out, but having checked out the DVD, I must say, I really enjoyed it, and it made me miss those hand-drawn animated features. This movie is the best example I've seen of combining 2D and CGI animation, and I didn't even realize that the character of John Silver uses elements of both until I'd finished watching the movie and moved on to the special features.
The visuals will stick with you a lot longer than the story elements, but 'Treasure Planet' made me nostalgic for the second Golden Age of Disney animation.