I just read this http://www.truthcoin.info/blog/mining-heart-attack/ and it dawned on me how incredibly cool PoS is. Peercoin will never ever have this problem, but it is very likely that Bitcoin will. The author argues that this is most likely to happen around 2020- something and I maybe by then a Bitcoin “heart attack” won’t drag AltCoins down with it because there will be enough awareness surrounding the technologies. At least I hope so 