In a recently opened "questions to developers" thread on the official Nival Interactive forums, Nival has answered some Heroes V questions. The answers are as follows:
The first patch will be out soon™.
The Russian version of the patch will be 39 MB big.
The map editor will be released no later than August.
The random map generator will appear after the editor.
It is possible that combined artifacts will be introduced.
The possibility to load/quit during a battle will be added soon™.
A more detailed manual with gameplay mechanics is in development, it will be available as a free download soon™.
New maps will be in the second patch, soon™.
The first patch will make it possible to play over a segmented network, but a direct IP patch isn't yet planned. They'll consider it if they get spammed with requests to implement it.