From what I remember Roald Dahl really disliked Willy Wonka and the Chocolate Factory, and this new movie was largely an attempt to make a movie based off the book, it is meant to be a lot closer. I hate it when people think this is a remake, it is simply an attempt to adapt the book to film again.
[edit]I seem to remember reading an article that mentioned that the writer of the new script had never actually seen the old movie.[/edit]