Meta Head template for Blog

Hi,

The Meta and Social tab for blog posts is a very welcome addition.

However I'm not seeing any of my changes to meta_head.html being implemented. We've allowed to change this right?

I'm just trying to add some common other meta bits

E.g

<meta name="description" content="<perch:blog id="meta_description" label="Description" type="textarea" size="xs" escape="true" />" />

<meta name="keywords" content="<perch:blog id="keywords" label="Keywords" type="textarea" size="xs" escape="true" help="Separate with commas" />" />

I've also just tried updating one of the templates existing titles and no luck.

I'm updating templates/blog/meta_head.html