Once you have entered a chat room you will see all of the members that are in the room on the right side of the main window, also known as the 'group participant list'.
The person who is speaking always shows on the top of the list in the 'talking now area'.
Next are the people who are streaming their web cam video to the group.
After them we find those who are 'chatting' in text. The folks chatting in text can also be 'waiting' (top right) in line to speak.
Next, you would find users that are 'restricted'. Restrictions can be placed on guests by the 'admin' of the room. You can identify the 'admins' by the gray logo beneath their name in the participant list.