lennaert - Yep! You enter as a group and the theme is released just before the competition starts. Then you all get together on skype or whatever and try to design a game around the theme. Decide your roles and goals and get into it!
It's obviously very intensive as you only have 3 days to complete your entry, so if you are interested we should at least try to set up our workflow ahead of time. If you (or anyone else) wants I can walk you through the SVN client setup that will take a minute and we can make sure it's all functioning and set some ground rules.
The team owns the game (it will not belong to Ludum Dare or anything) and you can keep working on it afterwards if you wish, but mainly I just want to do it for fun and experience (I have enough projects ongoing at the moment).
So an example: theme is night-time, GO!
Spend 3-4 hours outlining design
Get to work
Sleep for a week.
Or at least that's how it was last time. Last time we made something with a great core, but too bug ridden and not put together nicely. So it's important to control your scope and make sure you have good workflow if you want to get it shiny.