It's basically a chat room with some graphics and Mafia mechanics installed.
A default game is 13 people, with a LOT of roles- generally everyone has a role (I know, I know).
Rounds are essentially a minute long- 30 seconds of discussion, 30 seconds to see if anyone wants to vote, 30 seconds for a "trial," nighttime is 30 seconds, etc.
It's surprisingly addictive. And a game is quick, so.
Some more advantages:
Random lynching is actually BAD, here- because there are so many roles, townies can generally get some sort of information at night.
Every character has a "Last Will" It's basically a notepad that you can type on, and when you die, everyone else sees it. That means no more hypocopping!
Choose your own name for each game. When the game starts, everyone picks a name. That means there's none of the "Oh, Isaac was such a good player, let's kill him first" nonsense.
Achievements! They're kinda dumb, but I did get a little thrill when a thing popped up after I had won as Serial Killer.
Anyway, check it out.
And while I doubt many people will see this, I miss the games we used to play... sheesh, 5, 6 years ago? They were pretty great.
-Dan