I did not see the editorial yet, but my opinion about the cover so far is not very positive.
I am not a fan of Vogue Brasil to get started; they often choose some not so good models as their cover, they try to push up people that are not worthy and they continuously publish cheap looking editorials.
Yes, Kate is a fashion icon, but it doesn't mean that she will always look great and elegant. Depending on the styling, posing, light and location, even a shoot with Kate Moss can look bad!
Lately it seems that she has been shooting very frequently naked or in over provocative style. Those are some pics of her editorial in the Vogue Italy December 2010:
In my opinion, what separates those pictures of Kate and the pictures of some random porn star, is her fame. We all know fashion can be really sexy and provocative, but it also requires good taste and elegance to stay "fashion".
In the end, this is just my opinion! Maybe the editorial will look great! Let's hope so!