I read through the Indieweb criticism and Small Web pieces I linked yesterday. Both are interesting and make good points, as does the Indieweb movement itself. But all of them share what I think is a common flaw: they're too technology focused.
For an indieweb-like idea to succeed beyond a niche following, it needs to solve the problems of normal, non-technical people. What brought normal people to Facebook? Among the main reasons were discoverability, aggregation, and extreme ease of use. Discoverability means easily finding friends & being found by them. Aggregation is the news feed: combining all your friends' posts into a single time-ordered page so you can scroll down and catch up. And the essential tasks were so easy to do in Facebook that everyone's mom could do them all by herself: signing up, finding & following friends, reading posts, creating her own posts, commenting, pressing the Like button, etc.
If I had to pick just one feature to start an indieweb, it would be discoverability. That's the killer feature; that's the core thing that made Facebook useful to normal people: suddenly, you could easily find your long lost friends from high school, and reconnect.
Without a user-focused discovery mechanism, these well-intentioned indieweb efforts are going to struggle to move beyond their small niches.