My personal opinion (may be wrong, I'm not perfect)
ATTENTION:facts:: the views I will post here and their comments may reflect my ignorance or Google translation errors. Ideas or statements that I present can be quite false or misleading, products of my imagination or my common sense, or little knowledge. Sorry for my bad English.
My view is that Elon Musk's statements were created to increase the value of the shares of their companies (like Apple and Mavericks, describing it as "the best operating system in the world"), not for reflect a real goal. Remember that is a trading company that seeks commercial gain. I honestly do not think I have as a goal to improve or enrich (in any aspect) humanity.
Regarding the trip to Mars (and subsequent colonization) I think is very soon (not saying it's impossible within 100-150 years). I think things that are done in a hurry are not good results.
I think about the first manned mission (space agency, private company, etc.), I think it could be done if you have the goal of reaching, not only for economic benefit (in the case of a company), that if be performed (I mean take astronauts to Mars and bring them safe return), it would benefit (economic and otherwise) from really biggest form.
I think the first manned mission to Mars should also be raised in order to bring them back home (I dislike wake up in the morning and see a dry, monotonous and bleak atmosphere, instead of the varied landscapes of the Earth, among other many things; besides knowing that long for the rest of my days I will see a desolate landscape), without doubt the latter would cause psychological, and moral problems very bad, which in turn would bring disrepute to the public of Earth, which the case of a state agency that will send astronauts to stay up to Mars, they would not do anything other than waste the tax money that could be used for other purposes more available and more relevant to society.
I think a colony on Mars should be considered once you have solved problems on Earth that are evils of mankind (disease, poverty, etc.). So once stabilized (in a way, or so that it generates the least amount of problems in the future with the habitants of Mars), if you could consider extending humanity to other destinations (Mars, etc..) Although I think the first should install a permanent base on the moon, and then another on Mars. We should go step by step and not fast, because it is a very sensitive issue (talking about life, not of money that is an object with symbolic value). We should think in the humans life's, not so much in material losses.
Furthermore, with respect to space exploration by private enterprises, I think is an excellent idea. For example aviation and aerospace exploration could create new jobs, scientific studies, discoveries, etc.
While not used as told in the book Red Mars by Kim Stanley Robinson, and the example of the fictitious companies Subarashi and Praxis.
Nearing the end of my extensive (and perhaps useless comment) this theme of Elon and its future projections, remind me the history of 2001 A Space Odyssey, saying that in 2001 would come to be able to travel to Jupiter, and actually today day can only get astronauts to the ISS every three or six months (or even more).
He finished my comment.
Greetings to all who made this thread is very interesting to read, full of information and enriching exchange of ideas:thumbup:.