You might want to tweak the poll options a bit :wink:.
However my two cents on this is I don't believe having individual birthday threads creates all THAT much of a problem considering they are contained in the "off-topic" section which tends to have a lot of fluid movement as is.
While having one thread for all of the birthdays may seem convienent for space reasons, a major problem could arise in the fact that once the thread gets to 10+ pages, people may not want to fish through all of that to see or post birthday wishes, or if they wish to save them and what not it also could become problematic.
I do see the point in having one thread, as if you want to say something special to a person you could always PM it to them, but I don't see a dire need to change things from the way they are now personally.