Aside from the MySQL vs. Other DB debate (which I refuse to take part of, although I'm willing to ascribe good points to all camps), this article is absolutely excellent with respect to acting as a guide for people who want to use MySQL as a Key/Value store. Absolutely stellar article! All of the points are dead-on. I applaud the author for putting together so much specific information about tuning MySQL for Key/Value in one place, and the ridiculous speed and scalability you can get if you do it correctly. (That being said, NoSQL Key/Value databases are good too.)