I don't see why most of the comments are negative. This cartoon actually makes you think and actually has a serious plot. I mean, look at Sponge Bob Square pants! It isn't a show full of nonsense and crap, it's beautifully animated and challenges the little kids watching it to think and try broaden their perspectives on different situations.
Sure, it has it's cheesy morals about understanding and friendship and unity, but it has to or it wouldn't be considered quite appropriate for young kids now would it? But it still retains some of the melancholy, beautifully depressing atmosphere Adams gave his masterpiece of a novel.
Watership Down's a great show. You should at least watch a few episodes. And the second season, though straying greatly from Adams' novel is still good. More action-packed and a more creative story line, now that Adams' story line is done and they can expand with their own ideas.