How about this as a generally simple idea.

On the left hand menu there should be numbers alerting us of changes... In example

Forums (+1)

Ranking (-15)

Friend List (+1)


These are just examples of what it could look like. It could tell you how many levels you raised or dropped within a week without having to go to the leaderboards.

With the forums, it would inform you of how many new posts have affected you or maybe that have been posted since you were last on...

Friend List would tell you if you have a new friend request without you having to remember to check it occasionally.

You could go on from there, just an idea.