Does the Sitecore CMS allow for meta-data tagging using the schema.org taxonomy?
Yes it does.
And pretty much any other taxonomy I can think of.
Sitecore allows you to organise and structure your content in any way you see fit, including the adding of additional metadata to support both internal and external searching and filtering.
A few references, but there would be hundreds out there:
That said, you may in some cases need to expose this tagging to your HTML, so full support for something such as schema.org does require a modest implementation effort. It really depends on a lot of things; schema.org covers a lot of different things, like dining reservations to volcanos.
Can you please clarify the purpose of such taxonomy?
The purpose of a commonly recognised taxonomy is, that it allows external sites (like search engines and browsers) to better understand the content. Like for instance, if Google knew that a particular button on your restaurant page leads to "Reserve Table" (and understands what this is) - it allows them to provide any user with a better link and experience, if a user was searching for "dinner reservations". Just as an example.