I personally believe that there will be no "KotOR 3", and that the internet gossip is all psychological. If you have happened to noticed, the 30th Anniversary celebration for novels, comic-books, and games was flatline. If I had a franchise that was 30 years old, and had a large fanbase, I would do some spatacular things. When it comes to the "Knights of the Old Republic" game series, I personally believe that "KotOR II" was endgame. LucasFilms and LucasArts are too busy making stuff for other media and movies. Yes, there are a few tv-shows arriving for Star Wars, but most of their efforts are on Indy. "Force Unleashed" is getting most of the Star Wars gamming attention.
"KotOR III" is a myth.
R.I.P. to 'The Source' and 'MacCorp'