On Hotmail Blog you can find a new set of screenshots

From those you can see the lack of huge ugly image banners. I hope they will stick to that and is not only for internal testing.

Anyway those movements should stimulate the Yahoo Mail Team, to roll out the beta mail for he general public.

Edit:
Regarding image banners there is a beta user saying:

I haven’t been able to create nested folders yet. The screenshots above are slightly deceiving though, because when the ads come in they take up both header and right side screen area.

Heh I knew it was good to be true. Aren’t they learning the lesson? Gmail among other things has perfectly integrated ads that don’t disturb the user, and that’s why it’s so popular.