Those features are announced in Celestian haevens !
Well now we know the second expansion name !
The Winds of War. The title will add a collection of new features such as:
1.Customizable Object Paintbrush
2.Campaign Editor Help file
3.Customizable spell lists in the Conservatories
6.Add/Remove underground level on an existing map
7.Water passability indicator
8.Editor remembers your window layout between sessions
Hmmm. I wonder... What is connection between weather and Heroes IV ? (Gathering Storm, Winds of War)