I won't directly point a finger but there's a post in the buy sell forum that caught my attention earlier. The OP posted a tease offering permanent PR 9 backlink but he didn't share all the details because he was in a hurry. He promised to update once he got back from dinner. By the time the OP got back from dinner, tons of people had posted telling him they were interested and asking him to PM the details. The OP then kept his promise and updated the starting post with the information. So what he ended up with was a post with many replies demonstrating interest in what he's selling. The people all posted interest before they knew what he was selling, but anyone who didn't happen to see the post before he updated it wouldn't know this and would potentially be mislead. Is this a common practice?