What is a name?

I've been using the term "Moonfire Games" since I legally changed my name in 2000. I even have a domain (http://mfgames.com/) that uses that name and it shows up on pretty much every search term for "Moonfire Games". So, imagine my surprise when I do a random search for Moonfire Games and I find that someone created a group called MoonFire Games at http://moonfiregames.com/. According to the `whois` record, they registered the site in 2008. Eight years after I started using Moonfire Games. I assume it is either an honest mistake or oversight. But, I also worry that it is something more. Not to get against me, but simply because moonfire is a cool name.

Its annoying, since it means that I either have to trust in my fellow man not to abuse using the same name, risk the chance of not being able to use it anymore, or to defend it. Part of me says defend it, mainly because some of the things I've been waiting on have finally happened (I moved to Iowa) for creating my own S-corp and getting a proper trademark.

Its frustrating that someone would have done this. Part of it is my own fault for not really pushing it myself, but I'm kind of mixed on what to do.

EDIT: Actually, I got a very nice response back from the other Moonfire Games. It looks like we can figure something out, so it isn't such a terrible thing. It really helps when you don't respond negatively in emails. Though, I probably should incorporate Moonfire Games anyways, just because I've been using the name for nearly a decade now. And using it on my GenCon badge. And my emails. And my forum... :D