I've been generally curious about DDG for awhile now and I'm still trying to figure out why I should make a switch. If I understand correctly; DDG is trying to solve a problem in internet search so that people can't find things easier on the internet without sacrificing knowledge about one's self or behaviors, and your organization believes that that problem is largely due to the opt-out nature (or rather how you are automatically opt-in'd to everything) of Google's platform.
Also, the filter bubble it is not an effective marketing message because it requires too much education given it is a complicated subject no one knows about.
I guess, I, like many others who have expressed interest, don't see the problems with this. More commonly, I can't say my mother or my boss or anyone else I know is encountering this as a problem or a challenge. I'm happy to be wrong.
I find this whole topic absolutely fascinating, especially after having recently read Nudge by Richard Thaler, which basically is a whole book which talks about the value of libertarian paternalism. In other words, how opt-out choice architecture can be much more suitable than having completely free choice. Would love to know your thoughts. Great blog, this is fascinating stuff!