I've registered a couple of custom taxonomies to go with a couple of custom post types but I'm having some trouble getting a template file to work.
I've tried taxonomy.php, taxonomy-[termname].php, taxonomy-[taxonomyname].php but none seem to register and the link reverts to index.php
You can see an example of this here - http://wordman.deanelliott.me/portfolio/ just click on any of the links inside the yellow box and instead of going to a specific taxonomy template page it uses index.php
I'm not sure if it makes a difference, but this is the code I'm using to register the taxonomy
register_taxonomy('cat', 'portfolio', array('hierarchical' => false, 'label' => 'Category','query_var' => true, 'rewrite' => true));