That's easy to answer -- TED is to ideas what sugar is to nutrition. One has a superficial resemblance to the other, a resemblance that lasts about 30 seconds.

The article points out that it is more the style of the organization rather than the actual content which draws critics. I would say that's a fair assessment- I don't see any harm in spreading information, it's the audience's responsibility to take it with a grain of salt.