Right, exactly. There is no evidence in the gigaom article that there is a problem needing to be solved. Whether MySQL is "what's causing the problem" can't be evaluated without that. Facebook does, pretty much, work. I am not aware of any major complaints for users where MySQL has been traced as the root cause. I am NOT a MySQL fan, far from it, but if it's working, then why talk about gloom and doom?

While everything you say about MySQL is true, Facebook is using it in an extremely simple way: as a persistent key-value store, according to the talk they gave at MIT. That circumvents a lot of MySQL's weaknesses. Now, you might ask, if that's all they want, why not use software specialized for that? Well, I'm not sure, but (a) maybe they do use a bit more than that, such as MySQL async replication, and (b) I have heard from some people that MySQL (InnoDB) is actually surprisingly fast as a key-value store, though I do not particularly know why that would be. So although what you are saying is excellent general advice, the Facebook situation is very atypical.