I just recently got more active in the hub community by answering questions. I had never seen that tab before. It's a lot of fun.
Since I started, I have gotten many followers and my score has increased. I've also noticed more traffic to my hubs as well as comments on them. I know when it comes to blogs the search engines love activity so I am assuming that I will start to see my hubs performing better in the days to come. Fingers crossed :)
My question that arises from yours though is...if the hub activity increases on my hubs will this not also increase the positioning that the search engines would give my hub?