Out of personal experience, this large number of players won't last for very long. There's usually a mass-dropout a little after the IC starts. From there, one of two things will happen:

1) The RP dies from the dropout wave.

2) (I'm hoping this) The RP survives the wave and stabilizes around 3-6 active members, depending on the RP. Once it stabilizes, it lasts a VERY long time (I've hosted the same RP for about a year once. T'was pretty sweet.). I've found that Skype helps hold people accountable, since the message is instant and you get a notification. I'm not going to force anybody, no, but I've found it to be extremely useful.

Another change of topics: Anyone up for team-forming with me? :D