The other major scalability limitation of Microformats, that is not going to be fixed, is the issue of vocabulary term collisions. Microformats do not have namespaces and in fact, namespaces are considered harmful in the Microformats community.
RDFa employs prefixes in an attempt to ease authoring of RDFa web pages and to provide a mechanism when differentiating between vocabulary terms. This means that two people can use the word “title” in their vocabulary without clashing. Not so in the world of Microformats, “title” means “job title” and even though there have been many attempts to change the definition of “title”, it has stuck. This means that if someone were to create a Microformat-like vocabulary that used the word “title”, not only would it go against the definition set by the Microformats community, but it would also confuse the Microformat parser if there was also an hCard on the same page.