Microdata - to my understanding this is HTML 5 markup inserted into pages. If this is the case, based on the user requirements you can incorporate HTML 5 markup on your pages using either custom user controls, or even using the HTML mode of the Content Block control.
Dublin Core - you can add custom meta tags to your pages either from their Title & Properties. In Advanced options
section you can define custom meta tags for your pages. Furthermore you can create your custom base page type and make your pages inherit from it. More information on the base page can be found here
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items