Woo, I'm so glad that I read this in the latest article;
Thank God it's 50 groups again, it's such a pain when I had to unjoin a group, then join another, just to get through some gate :S* The Group limit is now 50 000 members per Group
* VIP members can now belong to 100 Groups
* Non-VIP members can now belong to 50 Groups
50,000 limit is amazing though - the most I've seen on 1 group is 'answers' which was something like 24,000. (The official guides group had 100k + though, so meh.), much better than the previous 500 limit or whatever it was.