type attribute in the email element: Idea was to specify "text/plain" or "text/html" as used by some e-mail applications. However this is not any more relevant, we have passed the 1990's. So the type attribute is dropped and then the e-mail can become a simple string with format "email".
type in the rights element was misleading and has been dropped with schema v1.1, as well. Thanks for pointing it out.
Now a property's value, if it is of dataType "xs:string", can have an attribute with enumerated values "plain" and "xhtml". I had considered to use official mime-types "text/plain" and "application/xhtml+xml", but those are defined for use with documents and not for text snippets.
When writing the documentation of the SpecIF-metamodel some questions came in my mind: