ergophobe - 1:27 am on Sep 1, 2010 (gmt 0)
Well, if you're trying to backup your customizations, you can use it just fine for Wordpress and use it to merge your changes with updates, but it basically means not using the WP auto update feature. You'll need another process.
I have my WordPress and Drupal sites run a cron job that dumps the DB and gzips it and emails that to a dedicated GMail account for that site. That creates a DB archive, but you'll need a diff tool to see differences between versions and there's not much point to using SVN to manage it.