Honestly, I think groups are just going to pop-up here and there to do tasks/events/raid(s). Just this week, after joining, I've been in the raid with two different groups. One we started from the beginning, the other I jumped in to try and help with Atheon while I could. Seems like a good number of members are just actively on the Group Wall looking for groups. I would recommend just frequenting there and posting if you're looking. I'm all for scheduling, especially since people span time-zones and have different schedules. Though after my experiences this week, it'll probably not be uncommon for a group to start and not finish, and the same group might not be able to get back together later, so others will join to help. So, just try posting a bit before when you want to go for it and there will likely be people who want to join.