Newbie readme, bold, sticky...read! Are you just lazy or something?
Yes, you got me. A total waste of space. So how many posts is it?
To become a member you need 15 activity.
Activity is calculated:
The activity number is determined in this way:
time = number of two-week periods in which you've posted since your registration
activity = min(time * 14, posts)
Activity is updated every 30 minutes.
https://bitcointalk.org/index.php?topic=178608.0