Are you sure? I think it may just be confusing because the post count isn't static...ie right now this particular post is my 670th, but if I post another message, this one, along with every other post I've made, will say 671. It's not a snapshot kind of thing where you can go back and be like, "Hey, this post was my 100th!"
Which I like, because it means I will never have a post that has the evil numbers.