Athletes: I think pro-athletes in general are drawn as spectators to MMA events, expecially the younger athletes or ones in extreme sports. Mike Tyson is a huge fan of K-1, Pride and UFC and is going to fight. Gov. Ah-nold has a kickboxing/grappling tournament in his name (Arnold Classics?). I would think that football and basketball players are huge fans of MMA (no pun intended).
Actors/Entertainers: Same as athletes; Vin Diesel was at a previous UFC and made pre-fight commentary. Generally interested in MMA, but more for the younger crowd (except maybe Jack Nicholson)
General Public: Mixed perceptions; some look at it as uncivilized, some are neutral and some are luke warm. Its interesting when you find out Chuck Liddell was a former accountant, Carlos Newton is entering med school and other combat athletes (like the Klitschkos) hold PhDs in sports medicine because the general perception is that MMA is for brutes without brains. If anything, MMA could be tied to courage and work ethic.
Guys like Royce Gracie, Sakuraba, Roy Jones Jr (boxing) and Genki Sudo look like pushovers if you subscribe to the belief that only extremely large, mean looking guys fight well.
Tank Abbot, Paul Varelans, Butterbean and Kimo certainly have the image down but have mediocre MMA records at best. Regardless, their extreme size/personlaity attracts awe strucken Japanese viewers which rake in the dough. Its like a monster match come to life!!
Did anyone place any bets on Butterbean beating the crap out of Sudo

?