I don't see the problem.
And for those of you who though she was much better looking in Spice girls.. SPice girls is the group that made such a short dress famous (Geri's union jack dress had the same "cut" as this). THis dress should've been 2 cms longer I think, but it's not that bad. Her waist looks amazing in this.
Honestly, you should be glad that someone's actually daring in fashion, it's something there's too much of today... And some experimentation always will lead to strange and bad results, but it's what keeps the world going.