So does the post count reflect the number of post a person has as of the time that I'm looking at the person's post, or is it the number of posts the person had when they made the post? I think it updates, retroactively, everytime you post. So if ABCFlyer made post #12 in 2003 and post #878 today, I think that the 2003 post would indicate 878 posts if I looked at that post today.

I think that's just wrong. I mean, back in 2003, ABCFlyer was an idiot with only 12 posts, so you've got to take his/her advice with a grain of salt. But today, with 878 posts, what ABCFlyer says is pretty much gospel. Right?