My experience as DM was that there was next to no player interest for romance in my campaigns so far. I wouldn't be averse to PC/NPC realationships at all, as long as everyone is mature about it and there's a clear "fade to black" line.
For me as player it's similar. All but one of my PC's have been very unsuited for romances. One of those, a hart shelled but heart of gold avenger type was once approach by a PC but not all interested.
My one PC that could have been suited for romance would have been very interesting in it, but sadly he ended up in a one shot. He was a NG character whose prime goal was to create his own realm and a very tactical/manipulative/political thinker and even in that one session he was looking for some young upper class ladies he could woe to increase his status. He would have clearly used his romantical contacts, but being the good guy he was, he would have tried to be nice about it and would have been caught somewhere between guilt, actual atraction and drive to find an even more advantegous bride.