Not to sound like a total fanboy or anything, but something I’ve grown to love about the *World system and it’s focus on the conversation over narrative is that it actually uses OOC knowledge to invest the players in the game.
In most other games, the GM chapter often has quite elaborate sections about why meta-gaming should be avoided, and it’s often accompanied with advice on how to do so.
The “setup phase” for the play-by-post game I’m in has just ended, and we’re about to start actual play. I know a lot of things about the other PC’s that Roklo, my six-armed White Ape Wizard, doesn’t have a clue about yet.
I really like that, because now I’m interested in those characters and their goals, and I want to see them conquer their challenges as much as I want to defeat my arch-nemesis Breko, whom they know of only out of character.
Meta-game knowledge is a tool like everything else. Just as you wouldn’t use a hammer to straighten glass, you should use meta-game knowledge as an in-game motivation. It’s all about using what you have, when you can use it for something great.
I just wanted to get this out there.
DISCLAIMER: I do not mean that the *World system avoids narrative, rather it ignores it and lets the conversation shape it.