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.
Reviewed status of LC specs:
Discussed grammar of @page wrt @margin-box rules. Created CSS 2.1 Issue 71 in response.
Resolved: @rules inside declaration blocks are ignored if between declarations (i.e. at the beginning of a declaration before the property), invalid if within declarations. (CSS2.1 Issue 71)