Surprisingly, I've never heard of it. I've been playing and watching MMOs since as early as Ultima Online. I just watched a video of someone playing Realm Online.. and good grief.. it's about time for it to be benched.
I can't believe this thing is still around. It was the first "mmo" I ever played. It wasn't really even a game when I played it, you just walked from one screen to another and saw other people. After a few days there were areas where high level characters just walked around naked and chatted sex noises.