You also have Paris Video Game Development Group (
http://www.meetup.com/PVG-Dev/) which is well established.
Actually Paris Indie Game Dev Meetup and PVG-Dev have partnered up to schedule the same meetup at the same location the same day at the same time to get as many indie game devs together as possible.
Lot's of people organize themselves via Meetup.com so it's a great platform to get people with the same interests together. The site also limits search topics to 15 so having 2 meetups working together using different keywords extends their reach.
One thing both meetups offer that Paris Dev Night doesn't is that they are open to anyone. Right now Paris Dev Night explicitly states on their website that their meetup is not for students, so if you're somebody who wants to work on an indie project and has got the skills but not the past experience this is a great chance to meet people.
Maybe this meetup will even get some people together to make an awesome game, who knows.