Well she seemed okay with it - or royally proper in expression - when it happened
http://www.comicboards.com/php/show.php?msg=fantasticfour-2011072803120772
but AFAIK there has been little satisfying introspective followup by Medusa on the issue of polygamy unless she is sincerely and Inhumanly fine with it. Plus, Black Bolt has not said anything about the marital details/duties yet. Okay, that last sentence started as j/k but with the 2(!!!) recent methods of actually speaking safely has been presented, revelations could happen that the readers hear from the horse's-husband's mouth.