@digitsu - i think that's what he meant, that they are less likely to join.
CD is inevitable. but there are a lot primarily in the games with newer players - this is because people join the site, and either don't like it so they don't come back or they aren't doing well in a game and so they abandon it. it's safe to say, i think, that most more experienced players wouldn't do that, so when they CD it's a result of unforeseen circumstances, and/or lack of planning.
@jamie - i like to play the game. yes, winning is nice, but i don't like to win b/c of someone going CD. so for me, whether its my ally or my nemesis, or someone on the opposite side of the board, i don't care - CD makes the game less enjoyable. a game can still be enjoyable with a CD, but it definitely takes away from it, in my opinion. and although i am fortunate to not experience many these days, when i first started playing on this site there was a CD in every game it seemed. sadly, even in some games where the players are very experienced, people CD.
i think trying to reduce CDs is really good plan, and if there are particular penalties, that would be ok with me. i like the idea people have put out a number of times of allowing you to set as a restriction for people joining a game how many times they've gone CD but that won't help with the new folks who haven't yet. i guess the real solution is to organize games with players who you are confident won't CD, but even that isn't fool proof - i recently lost a game that was well organized and had a very committed group of players because of 2 CDs in the game.