"Mars One is essentially an interplanetary mashup of X-Factor and Big Brother, with candidates being selected by web vid audiences and the whole mission being broadcast live 24/7."
No it isn't (my housemate is an applicant so I have a good source). While it does plan to be relaity TV, that's actually in this case simply showing 'real reality' on TV, not people acting like idiots for the camera. It's designed as a very serious colonisation mission - nobody would get to go purely on the public vote, the public would only influence which of the pre-screened people get to go on the arduous and very thorough training program, teaching them everything from medical skills to toilet management.
I personally don't think it's going to get anywhere, but please don't believe the sound-bites about this being "big brother in space" with all the negative connotations this implies. The people applying are physicists, nerds, etc, not loudly gay morons.