Okay, so there were a number of new towns mentioned in the novels. I've picked out a few:
Mortal, Mountain Watch, Ione, Sweetwater, and Easterbridge.
Mortal and Sweetwater, presumably, are at/near their camps on the Oblivion world map. Mountain Watch is somewhere along a straight line from Cheydinhal to Vivec, close to the border with Morrowind. Ione is presumably along the Green or Red Ring Road, close to Pell's Gate. Nothing on Easterbridge, other than its closer to Sweetwater than anything else.
Thinking on Mortal and Sweetwater, I've taken a look at the camp's names and subtracted any that are obviously not the name of a town (i.e. someone's name).
So possible towns include: Atrene, Bawnwatch, Bodean, Bogwater, Brotch, Ales, Collarbone, Crestbridge, Fisherman's Rock, Garnet, Mortal, Nayon, Seran, Sercen, Sweetwater, Trossan, Valley View, Varus, Walker, Wind Range. BTW, Sercen, Nayon, and Seran sound Aylied to me.
It should be noted that there is an unnamed fishing village across from the waterfront, built upon an Ayleid ruin, that is mentioned in Lord of Souls. Could the Ayleid ruin be Fanacasecul?
On an older Redguard map, there also the label Vergayun in the area of Sweetwater. Is that a town or city? And is is substantiated anywhere else?
The West:
Furthermore, in Oblivion it is mentioned that merchants in Anvil have ports of call in Hammerfell, Summerset Isle, Yokuda, and the Western Islands. Where are these Western Islands? Is he talking about those islands seen separated from Yokuda by the Sea of Pearls?
Elsweyr:
What river is Riverhold situated on? I haven't come across one map with it situated along a visual river, but given the relatively feasible action of extending an existing river to it, could we say...White-Rose River? Or the Larsius River (better situated for Rimmen?)
Also, next to White Rose River there is another river. Name? Given that there's two rivers merging into one, I'd say one is called White River and the other Rose River, merging up to form the White-Rose River. But then, which is which?
Are the badlands of Anequina a basin or a plateau or neither? "Rim men" suggests that its a basin, but do we have any more support for this?
Colovia:
What real-life environment would you re-purpose as an exemplary model for Colovia? Personally, I've speculated that it is similar to Patagonia. Have we heard from the developers what inspired Cyrodiil's landscapes? Or is someone really good with botany or geography and can identify the plants in Colovia/Nibenay with real regions?