That \"My expert rating*\"?

Heisenberg_
From activity.

From the amount of public manifestation of expertise in the form of content creation to the game, plus, possibly multiplied by some factor.

Useless crap.

The activity in sections of different games. Let's have a game MassEffect, you shake some fashion for her talk on the forum, takes screenshots etc, then the rating goes up.
Like so

If you want to raise it to a particular game more comment under news,forums, etc. associated with this game,as well as spread files,blogs, etc. to this game.