For what it's worth: The namespace for Diplomacy sites is pretty homogenous. (PlayDiplomacy, WebDiplomacy, etc.) We were originally PlayDiplomacyOnline, but that didn't solve the homogenous problem and was easy to get confused with other sites. One of the big things we were trying to do was bring some Web 2.0 sensibility to the game, so a cheeky name seemed in order.
We didn't consider the impact it would have on new or potential players but it doesn't seem to have scared many newbies away; in fact we get regular feedback that our site was easier for new folks to get into. Personally, I think knowing that backstabbing is a core part of the game going in helps soften the blow when it first happens.
Please don't read my comment as a criticism, I'm not trying suggest it's going to ruin the game or anything. It's certainly a much catchier name (and an -r ending is a nice tongue-in-cheek reference). I'm just always fascinated in the nuances of language and the subtle effect word choices can have.
We didn't consider the impact it would have on new or potential players but it doesn't seem to have scared many newbies away; in fact we get regular feedback that our site was easier for new folks to get into. Personally, I think knowing that backstabbing is a core part of the game going in helps soften the blow when it first happens.