Here’s a new feature you’ll unlock when your game gets over 100 posts (the game also needs to have been around for at least 2 months too).
Over 100 posts you’ll unlock the “Story summary” option on your game’s homepage. This is to allow long-running games to show an summary of the recent story, to communicate recent events to a new member without amending your game description.
Click “Add latest story summary” to add a new summary.
In 30 days you’ll be asked if you want to add a new story summary. By then the story in your game has probably moved on far enough for you to need a new summary.
Here’s a video demonstrating how this feature works.
If you want to know more about unlockable perks, there’s a full list here.