About a week ago, Nat posted Open Source NG Databases on O'Reilly Radar. That caught my interest because I'm playing with some "alternative" databases for some of our data at Craigslist. Don't get me wrong, MySQL is great. But MySQL isn't well suited to every use case out there either. (I'll talk more about this at the MySQL Conference.) Meanwhile, I left a comment on that posting about CouchDB an