I voted yes, even though I wouldn't use them too much (maybe on one or two chars) A lot of people want wings and they were probably super excited when they heard that they would be added. I cant say anything about Impressive Title right here, as I haven't played it.
Those who do not want wings, however, were probably annoyed when you announced it. When/(well now "if") wings are added, they may be annoyed or angry to some extent. Some of them may learn to tolerate wings, because obviously, if they're added, many people will have them when you log on. As for those who will not deal with wings, well, I'm not sure what they will do. You can't really ignore winged characters, especially if they are power playing/god modding others. (I'm not saying that every person with wings will start bullying those without wings)
I personally don't care if you add them or not, Feral-Heart is fun either way, but how long ago did you say they would be added? About 4 or 5 months ago? You can't go back on it now. People already are hoping for them (or not) and if you go back on it now they might be angry or disappointed about it. And, Im not trying to sound mean or anything, but you don't really have the best reputation around the forums and such. Just saying...