I’ve seen a number of people tell others that WordPress 2.5 will have little to no database schema changes. It looks like that is no longer the case as MichaelH has pointed out. Changes to database schema from Version 2.3 to 2.5. *Table: comments Changed ‘comment_approved’ to varchar(20) NOT NULL default ‘1’ Added KEY ‘comment_approved_date_gmt’ (comment_approved, comment_date_gmt) Added KEY ‘comment_date_gmt’ (comment_date_gmt) *Table: links Changed ‘link_visible’ to varchar(20) NOT NULL default ‘Y’ *Table: options Changed ‘autoload’ to varchar(20) NOT NULL default ‘yes’ *Table: posts Changed ‘post_status’ to varchar(20) NOT NULL default ‘publish’ Changed ‘comment_status’ to varchar(20) NOT NULL default ‘open’ Changed ‘ping_status’ to varchar(20) NOT NULL default ‘open’ *Table: term_relationships Added ‘term_order’ int(11) NOT NULL default 0 Thanks to MichaelH for putting these changes together. This information is especially useful to plugin and theme authors as it lets them know if their particular project will break.