I heard from Robustus Hax of MBC. The name SLebrity had been considered but there may be some Linden Lab involvement in the show, which may cause problems. Why? Because the word SLebrity is clearly a portmanteau of SL and celebrity, and the SL element is trademarked. There may be a case for LL to go up against MBC because of this.
I say "maybe" because you can't trademark a word, only a mark. The word slebrity (no upper case for the first two letters) exists outside of the Second Life universe. For example, on May 11th, 2006, a blog post appeared entitled SLEBRITY SPOTTING, with the words in a caps font.
So the word slebrity cannot be trademarked retrospectively, although maybe SLebrity can. I'm certainly not going to consult my real life patent attorneys on this - and those of you who have such people working for you know the cost involved! - but from what I know of past work with them, I bet slebrity is OK but SLebrity is not: The former predates Linden Lab's annoucement in 2008 about branding and the latter is obviously SL related.
I may have some challenges of my own at some stage. My name, Sigmund Leominster, is mine, and mine alone. My initials happen to be SL. My blog, SL on SL is a gray area, but I have it as SL© on SL™ because the first SL is my intials, and I can copyright these, but the second is an abbreviation for Second Life, for which I use the obligatory ™ marking.
My friend Seikatsu Koba is working on a logo for me. I think it should be fun to see what happens if his starts appearing in the Second Life press!