Near the bottom of that image (just below the "add" and "remove" buttons) it says 'Ultrapeer'.

You are running as an ultrapeer rather than a client. Some of the clients are other ultrapeers - most are leaves - single users connecting through you to the gnutella network.

LimeWire decides whether to make you an ultrapeer based on your bandwidth and the demand for an ultrapeer.

If you wish - you can disable yourself as an ultrapeer through Tools|Options|Speed|Disable ultrapeer capabilities.

As an ultrapeer, some of your bandwidth is taken up with managing the network and passing messages. You also get to see more information and probably have better search results.

So - this isn't a problem, it is working as designed.

Mark