There was also concern that for those who want "reach" and "to be found" that federation isn't a good answer. I'd argue it isn't hard to be found here if you want to be with Hashtags and Directories even easier than other places in someways. As for reach I think the walled garden lock-in of Twitter artificially inflates the reach of many accounts. To the extent federation minimizes that I'd say feature not a bug.
My own Mastodon instance. It was inevitable really. So far this instance is an experiment and where it goes from here is evolving. My interests are space exploration, aviation, technology current & retro, soccer (football), and general geekery.
For right now membership will be extremely limited due to hardware constraints and other concerns. Unless you know me in IRL your request will probably go unanswered nothing personal.