It means that there are to many Members in the group to look at on your friends list.
i dont like it there , i cant see my friends . its in my way . That is also untrue . a group cant have too many members .
The only problem I had today with Steam was it kept messaging me that someone kept restarting a game even though I disabled the displays. Weirder yet is the guy never quit the game so why it kept telling me he was playing Half Life 2 every 3 minutes for 2 hours is beyond me.