"Automatic Update" for fonts?

Hi,

I wonder about how update notification might work for web fonts; when
a new version of a WOFF font comes out, web authors might like their
tools to notify them, and an "updates URL" in the <metadata> that can
be polled could be a way to do this.... I didn't think about this too
deeply, the thought occurred to me this morning and I thought I'd
throw the idea up here; I have no idea how trivial/complex this would
be to implement.

-- 
Regards,
Dave