Now I did this two times: from 2.0.4->2.0.5 and 2.0.5->2.0.6. It was quick and neat. You don’t have to disable any installed plugin and reactivate it later. But surely do a backup.
And the way to do the patch is:
1. go to the Mark’s blog, and get the diff file. Remember, download the file and save as it is. Last time, I did a silly job, opened the file in the browser and did a “copy&paste”, which results critical error in doing patch, saying “hunk failed”.
2. go to the root file of the wordpress folder, issue this command:
patch -p0 < wordpress-2.0.5-to-2.0.6-changes.diff (or any corresponding diff file downloaded, Mark’s blog is offering patch file starting from 2.0.2. )