A lot of wire copy already includes metadata, but it's generally just in a header that accompanies the story.
What I was envisioning was something more like what is being proposed for the semantic web:
<name id="1394">John Smith</name> was elected president of the <organization id="2315">New Castle County Council</organization> on <date value="2014-12-10">Wednesday</date> at the <place lat="39.685881" long="-75.613047">county headquarters</place>.<source id="23" name="Mila Jones" title="New Castle County public relations officer"></source>
I also wanted to use the metadata to help copy editors trim wire stories:
<priority value="1">This amounts to de facto resegregation. <priority="4">(And we all know how we segregation worked out the first time.)</priority> If the school district still values integrated schools, it must act swiftly to correct this effect.</priority>
It turns out, though, even when you create a UI that lets reporters and editors easily plug in this metadata without having to understand XML, they are not apt to fill it in, because they are just so overworked as it is.
Plus, in order for this to work on a larger scale, you'd have to get an incredible amount of buy-in. You'd have to get reporters and editors to agree that it's worth their time. You'd have to build software to support it. You'd have to get all of the different media companies out there to agree on standards.
It's just ... not what the media industry is (or should be) focused on right now. They've got bigger things to think about, like how to find a viable business model.