This enhancement is related to ticket #6933, with similar reasoning.
- It's a little more secure if wp-content happens to also be outside the webroot
- It allows us to add WordPress as an external repository in other projects with plugins/themes/cache engines/database classes that sit outside that external repository (we do some of this with bbPress)
WordPress requires a few changes as there are a few hard-coded references to wp-content.
If we don't like the constant name I chose ( WP_CONTENT_DIR ), then that can be easily changed in the patch.
This will almost certainly break a few plugins where wp-config is hard-coded, but only when the blog owner chooses to use this feature. Naughty plugins should use API calls anyway :)