how interesting.
i usually post "to" the OP.
hm. maybe part of that relates to the kind of thread, and the content of the original post.
in another forum i used to frequent, posters had the option of addressing posts to a specific name or to "All". i found that really useful and have always missed that feature here. i think it helps avoid confusions. it minimizes misunderstandings where someone thinks a post was directed at them when the poster intended is as a general observation.