Today the W3C published new versions of RDFa Core and XHTML+RDFa. These versions are the result of 10 months of work by the W3C RDF Web Applications Working Group, and are expected to be in their nearly-final form. You can see the full announcement at http://www.w3.org/blog/SW/2012/01/31/new-rdfa-drafts-published/
You have three weeks to look these over and raise comments. Otherwise, forever hold your peace. We look forward to your input!