Played W2 on a 16:10 monitor and it was mostly supported from the start. There was an issue with some cutscenes or something I don't remember what it was, but it was fixed. I would assume that W3 is supported fully from the start.
Oh heck, you are right. I don't know why i thought TW2 had black bars, maybe just in the cut scenes or something like that.
I don't really pay much attention to that detail, whether a game fully support it or just add black bars, it's the same for me and doesn't lower my enjoyment of the game, so then i assume it won't have any