There is not really much there yet, but the idea seems to be aggregate all your information related to interaction/social-networking/communication in one place. One place under _your_ control. That's feature number one.

Then, it could present this information in a way that is actually comprehensible by mere humans. Keeping track of contacts/addresses/events/news/photos/videos/conversations spread up between Facebook/Hacker News/lesswrong/Flickr/YouTube/LinkedIn/blablablablabla is not easy.

It may be of much less interest to you if you like to just forget about what you've done in the past (as it is practically done outside the digital world). Or if you do have an actually working sync-solution cross all your communications means.

Besides having a better overview of my digital self through this, I think I'd use it to come back and convince myself regularly that yes, I also have said so immensely stupid things in the past.

I think it is a great idea -- but to make it useful, it requires a tremendous amount of work.