What I did (for Lyle and anyone else).

Usual caveats apply, if you’ve done a lot of hacking then YOU need to know what YOU’VE changed. This is all taken from the WordPress Upgrade documentation. Worked for me.

The Preparation
1. Backup your database and the files on your site.
2. Download the WordPress ZIP file for 1.5.2.
3. De-activate all plugins on your site (will make your site look funny until the files are upgraded). I’d suggest taking a note of them as well, just in case you need to upgrade them too (I didn’t have to).

Note: It is NOT necessary to run install.php or upgrade.php as no changes are made to the database. As with all WordPress upgrades, the contents of your /wp-content/ folder should remain intact and unchanged.

The Upgrade
1. Delete /wp-admin/ folder.
2. Delete /wp-includes/ folder
3. Delete all the wordpress files in the root directory where the root index.php file is found. DO NOT DELETE wp-config.php. Note: My WordPress install is in a separate folder, I deleted all the files in my “WordPress” folder, leaving the remaining folders intact.
4. Download and extract the new version.
5. Upload the appropriate folders – /wp-admin/ and /wp-includes/ – and the files they contain.
6. Upload all the files in the WordPress root directory to your WordPress folder.
7. Re-activate your plugins.

Done. Hopefully. Was a breeze this time round, the docs could still do with a little “dis-ambiguating” and I guess it’s about time I used my membership of the doc team to good effect!