I notice that with the new patch, if you have a group of four and you queue for a specific dungeon using the dungeon finder, it does a ready check, everyone says 'ready', the top right of the screen says 'group formed' and then.... nothing. It says 'activity complete' and never actually teleports you do the dungeon. We've been having to go on foot everywhere. Boo.
Hopefully in this patch they fixed the issue where if two groups were merged together for a random, only the two leaders received the XP and rewards.