What I read in PCGames was:
'each of the 5 big cities in skyrim will have a fancy flair. Riverwood to example is a rural city in which you find roughly built blockhouses inclusive a fitting sawmill. The city Markarth is a massive, in stone built stronghold with buildings standing on vertiginous cliffs and with waterfalls which gives you a breathtaking view. In Haarfingar, a port city at the coast, it's really busy. Even the from the series well known dunmer get an own settlement with a fitting, dark style.'
So we have:
Riverwood
Markarth
Haarfinger
Windhelm
What I'm wondering about is, that only Markarth and Windhelm appear as major cities on the Skyrim Map, so either the magazine is wrong or the map changed significantly after the oblivion crisis.
The magazine seems pretty confused. Riverwood is one ofthe 5 massive cities at all. It is a town (and not even the largest in it's hold, Whiterun is in the same hold (county)), described in another magazine as "A small spattering of buildings" and from the images we've seen, doesn't appear to be more than asingle street or so. Haafingar is the old name for Solitude, which is one of the cities. For the full list, see my previous post. The Dunmer settlement is probably Winterhold but could be a different place.