There is something to be noted here, however, and that is a lot of RP cliques that I have run into in the last 3-4 years have been of a mindset that "We don't know you, so you will get minimal attention/inclusion until we have judged you".
I normally do not advertise who I am, where. I very briefly had my AresMUSH @handle linked to a character, but removed it because it just grew more and more annoying to me. I do not play the OOC game. I, in fact, stay the hell out of any OOC conversations about a game or the players on it. I just don't want to see behind the curtain.
I agree with Ghost - there are people out there that appear (to me) to be into MUSHing mostly for the "OOC Game" or "metagame" as many describe it. They derive their fun out of the OOC interaction, for good or ill, and not the IC character stories. I say this because: 1) They very rarely RP (maybe once every 3-4 months, by their recounting), 2) 99% of their MUSH time is spent chatting and talking.
Some of those people that I describe and have talked to over the last couple of years, are the very people at the top rungs of a few games' IC structures. The IC leaders of the game. Not RPing. Not stepping down for the more actively-IC people vying for the position, either.
Having had more than a few conversations with players over the years, just in natural chats, it seems to be that this happens everywhere. As one said, "It is how MUSHing is."
So, as a result of this, I don't advertise who I am, where I play. I have no playlist. Not because I've done horrible things or been banned anywhere, I just enjoy my anonymity. I like meeting new people who may be old friends but I don't know it yet, but yet neither do they. Discovering great RPers and friends is the joy of the game for me, 50-50 with the great stories written.