These notes may apply only to older versions.
- There is no way to preview comments; does not seem to be supported even as an option.
- The comment form does not indicate what markup is acceptable.
- Comment threading seems to be turned off by default, as many sites do not support it.
- When upgrading, disable plugins and unused themes.
- This can be done by creating "plugins-disabled" and "themes-disabled" folders and moving the respective plugin/theme folders into them.
- More stuff here.