09/27/2007 – the demo version of Heroes of Might and Magic V: Tribes of the East was released.

So, Nival hasn't completely fallen into decay yet. It's just that, judging by the overall picture, the information there isn't updated very actively. Or maybe I just don't visit the forums often enough, so I haven't been able to find that coveted key.
Now I need to check out the new map. Thanks, Alan.

Added 4 minutes later

Here are the download links: http://www.ubi.com/DE/Downloads/Info.aspx?dlId=2345 from Ubisoft, and in general, most gaming sites already have the demo.

Well, yesterday I was on Fileplanet, waiting for the download to become available (and eagerly rubbing my hands), and today, of course, it's already available in many places.