Do you want to know how the CSS WG works? Fantasai has written about:csswg, An Inside View of the CSS Working Group at W3C.
The CSS Working Group has just published a new Last Call Working Draft of the Selectors module. This working draft addresses many comments that have been received since the last publication. The Last Call period extends until April 7th; please send any comments to email@example.com. Note that we will not be accepting new feature requests for Level 3. Assuming no major problems are found, we will be republishing a Selectors Candidate Recommendation in April.