It makes it to the table with my group of friends because it takes much less time to play than Diplomacy.
Just like Diplomacy, you may not want to play it with people who take the board game backstabbing stuff too seriously.
I was quite successful and lots of people hated me for having backstabbed them in previous games but that only made my game better. Having an opponent dead set against me was just barter for my trades with other people.
There is no other game like it, although I'm told Intrigue gets a little bit of the double cross feel.
If you're playing face to face and you see Russia and Germany go talk for ten of the fifteen minutes, it's no secret that they're working together. Online, it's much harder to tell.
Oh man, the emotional investment in this game is just never replaced by online play, imo.
I love the game in theory, but I felt too bad after backstabbing people. (So if we ever play, trust me! :-) )
It was shocking to realize how wimpy I really am.