We've had a couple of instances now where somebody was waiting for the right moment to post a Call To Adventure, and then somebody else came in and snatched up all the players in the tavern from them. Often it's because some people like to talk about the adventures they're about to run, even before they're approved, and some people like to sit on them and spring them as a surprise.
So let's say Bilbo submits an adventure that's supposed to have a surprising out-of-nowhere opening, and doesn't mention it to anyone in public until it's time to start it. Then Frodo submits an adventure, posts, "Hey, I just submitted an adventure!" and then when it's approved, posts, "Good news, my adventure's been approved, I'll start it as soon as there are enough people in the tavern!"
From Bilbo's point of view, this loudmouth is stealing his thunder - he's been waiting for the perfect moment to spring his surprise, and now everybody's talking about Frodo's adventure, getting a party together for it, and his surprise will just fall flat, even though his was approved first. But if he starts his adventure before Frodo does, then from Frodo's point of view, he's been talking about his adventure, getting everybody excited, and then out of nowhere this jackass posts an adventure that nobody even knew was coming and steals all his players! How was he supposed to know that Bilbo had an adventure waiting?
(The Fire! thread's been on both ends of this.)
So I think we should have a thread or wiki page with a list of upcoming approved adventures. They don't have to include the adventure name or any details, to preserve surprises, just the DM's name and the date they were proposed and accepted. That way anybody who's thinking of running an adventure can check if anyone's waiting already, instead of relying on people to keep track of who's mentioned they might have something coming up.
The thread should also list any other details about scheduling the DM thinks are relevant. (For example, if you have a quick adventure that you want to run whenever there are people sitting around doing nothing, like Fire! or Hoofchew, you should note that so that people can keep putting their adventures before you in the queue.)
We had an informal, "What adventure are you thinking about running?" thread, but it's dropped out of use, and I'd like something more official to post adventures that are definitely going to happen, not just in the