Its obviously progressed further than just a briefing map mock up. this is from the same source. You dont get pictures like these from Google.
To quote the post - "This is a view looking looking east towards Dordrecht along Haringvliet -- you have to use a little imagination. I might do the first ever IL-2 cross channel flight now." -- and according to a later post the flight was done. Doesn't seem to be much height data included yet, but its hard to tell when you are looking at the Netherlands, however looking at other mapwork which has been done issue of height data is not likely to be a problem. The ambition seems to be to produce a relatively unpopulated map, but with all the key geographic features included, so that it can be used for mission building. Looking at the earlier posts this seems to represent about one weeks intensive work. There are obvious flaws in the texturing but this doesn't claim to be ready for release. Its only a WIP screenshot.