Not a lot.
The arrowhead to the farthest left of those 5 in the top right corner of the page opens the buddy list in a new window. If you open that up, you can use the check boxes to send PMs, or click on their ID to see their profile.
On the main page, where it lists peoples names that are online right now, anyone on your list will have a "+" by their name.
That's about all that I know of.