units (in Presentation MathML)

Hi everyone,

Is http://www.w3.org/TR/mathml-units/ still the official suggestion on
representing units in MathML?

Throughout the examples, class="MathML-unit" is used in addition to the
actual recommendations. I'm guessing most tools that treat units (editors,
converters etc) add a class (or RDFa, microdata etc) as well and I'm
wondering if there has been some sort of real-world consensus on this.

Regards,
Peter.