Quoting Brion Vibber, from the post of Tue, 01 Feb:
MySQL 4.0 remains the recommended database platform for MediaWiki at this time.
I hate having to read into things. does this mean that support for mySQL will one day be the secondary or "less recommended" or even depricated backend? I'm only guessing but there will be a rather large number of users that will refuse a DB switch... also most hosting sites offer LAMP but considerably fewer offer LAPP...