I'm still set on coming, but whether a group is secret or not it shows up on your news feed on FB, which has been my experience in the past. I'm not 'out' on Facebook due to having some work colleagues on there who aren't in the know, some of whom I'm still not sure will take it well and I'm not ready to take that risk.
So, defintely want to come along but won't be joining the facebook group. Sorry.