Proof of Stake is worth being highly skeptical of. The fact that most people blindly support the idea when it seems to leave fundamental questions swept under the rug is worrying.

I wish I could give a further critique, but I'm not familiar enough with the subject. There have been several persuasive comments posted to HN on the brittle nature of Proof of Stake, and the lack of hard answers to basic problems. Tacking it on as "this would use even less power" is a sign that perhaps these alternate schemes (including the one in the article) should be taken with a dash of salt and pepper.