> Can't you frame every social organization in this kind of light?
This reminds me of the comment I recall from 'patio11's podcast, someone was talking about how their sales pitch uses a lot of spam-associated techniques like suggestive rhetorical questions ("Are you happy with...", etc.), and was asked (in order to give structure to the guest's pitch) something to the effect of, "What separates you from the spammers?" and his answer was, essentially, nothing except I deliver the goods.
I think in general this is the only sane answer to this style of question. Can't you frame every organization as a cult? Probably, if you word it carefully. Not the right question on either end, really.
Does TED deliver the goods... I don't think so. If these people truly have deep knowledge of their fields, <20 minutes is not long enough to really communicate that in general, and from the talks I've seen, while engaging and enjoyable, are not really informative. On a higher level, it's 2015 -- if I really want to change someone's brain so that it _gets_ my field, there will be e.g. interactive elements, which are largely missing from TED talks.