Control The Link & Powered By?

How do you control which link this plugin actually refers to as we have several main sites and we may want to change which link this plugin refers people to.

Also, this affects the link inside the meta widget displaying on a front end page, but why then does it use the phrase "powered by" in the description of the plugin? The meta widget does not display the "powered by" phrase. I thought that was used in the default footer area on all multisite generated blogs (as opposed to the meta widget area)?

If that is true, then how would I customize the default generated "powered by" link on the front end of all user blogs in the footer?

Thanks.