Well the upgrade to wordpress 1.5.1 seems to have gone ridiculously smoothly. There was a sudden heart-stopping moment after I’d set the upload to overwrite everything, when I thought that my config file would now disappear.
Fortunately the wordpress developers are very clever. You see, instead of having a config file in the install package, they have an example config file that you have to rename as part of the installation process. Thus meaning that a direct overwrite of wordpress installs does not overwrite your configuration. Genius.

Also the new themes system means that I don’t have to worry about the style of the site changing either!!