Sort:  

She mentioned that she voted on virtually every niche and probably suggested a number of niches. Also, she comments a lot on the suggested niches. That's how she earned her reputation, I believe.

Okay, so it's commenting on the niche suggestions. That makes sense. I know voting does a little bit too because my own reputation has gone from 0 to 3, but I haven't been super-active. I'm just now getting into it. Thanks a bunch.

Funny enough, I get +1 point to Simple rep for each approved niche that I suggested. The value changes several minues after the approval period ends. What will happen if somebody manages to sucessfully suggest more than 100 niches? )

The Quality analysis component is more tricky. At some point in time it boosted from 0 to 5 without any apparent reason and since then remains unchanged.

I went from 3 to 6 in one day just commenting on niche suggestions.