Not sure how many PHP frameworks use yaml but the one that I use, Symfony, does and it'd be very helpful to have some sort of syntax highlighting for it in PHPEd.

Thanks for reading.

I also work with Symfony, and would be very interested to see this feature as well - syntax highlighting of YAML lists, variables etc.
Also the option to create .yml file when File -> New is chosen from the menu.

I could be wrong, but I think you can get this now by simply putting a starter file into the templates folder inside the PhpED folder. Worth a shot, anyway, if you haven't tried it already.

To bad, that does not work.
I also work with .yml files and would like to add syntax highlighting!

it recognizes only files in Templates folder whose extension is listed in tools->settings->File Associations.
Feel free to associate .yml with XML or HTML type.