I'm just curious about WordPress using MySQL exclusively. MySQL is a fine database, but is there a reason that WP doesn't support other databases? Strangely, it looks as if someone started down that road, creating a wpdb class that abstracts the particulars. There are still plenty of references to mysql though. Did it turn out to be too much work?
A corollary question would be, what would the reaction of the WP community be if someone (not necessarily me) were to contribute code that allowed WP to work with another database?