Yes, the idea is to allow configuring of cross-site includes by passing arguments.

"Application" is a bit overloaded too and we'll see if it works. I admit to abusing that term already, using it for includes and for site templates.

If you have suggestions for clearer terminology, they'll be welcome. Perhaps we should kill the packages wiki and reuse 'packages' for cross-site includes.

I think cross-site includes will be a fantastic feature in its own right.
How will it work?

The design for it can be seen here.

@ Pieter, the only thing would be that cloning a category doesn't clone CSS for that category. But as you suggested, a CSS module would resolve that issue entirely.

Glad you like this stuff. :-) I want Wikidot to be the … shudder… Visual Basic of Wikis: a tool that lets us build apps for others, on a huge scale and very cheaply, and without programming skills. This seems the best way to get a Billion Happy Users.

Obviously that means making things most people cannot every understand or use, but this is fine so long as there can be clean separation between levels of difficulty.