[Squirrelloid]

MP etiquette:
1) Try not to stale
2) Don't just stop playing because you're bored/losing/etc..
3) Don't just set AI for the above reasons
4) If you must stop playing, find a sub
5) Don't suck more than is reasonably expected. (Failure to expand to at least ~10 provinces year 1 is inexcusably bad with most nations on standard maps and settings). Ie, some basic competence is expected. Less so in new player games, but even then, you can learn how to expand against indies in SP, so there's no reason not to do so. This mostly applies to expansion phase - getting clobbered while fighting against another player is part of the learning process with MP games.

That's really about it. Unless the game has specific expectations, diplomacy is based on 'how much do you care about short-term advantage vs. the diplomacy metagame', ie, Machiavellian with likely chances to reap what you have sown. Do feel free to announce whatever intel you think gives you an advantage, or trade it privately for profit. Make up intel when its to your advantage. Get on a soapbox and get your propaganda machine going. Whatever floats your boat.