Hi Peter, incidentally, I have only created three of those four categories today; they are there to gather--as one might guess by their names--Featured pictures, Valued images and Quality images as defined by the Commons community.
The local juries, and even the international one, are not related to this community process, and the Commons community does not need to wait for them to start or end their work; the juries also do not need to take the judgement of the community into consideration at all.
The GLAM category has been created by Maarten, and is intended to gather images of gallery, library, archives and museum buildings uploaded as part of WLM; it is my understanding that everyone is allowed to put his/her images there as long as they represent a GLAM building (though Maarten might comment on this further).
After the end of the competition, images gathered in that category will be reviewed by Europeana, and the winner will be awarded a special prize sponsored by that organisation. More information on this will be published on the international website on Sunday.
And by the way, if you're interested in all content from Wiki Loves Monuments that has been highlighted by the Commons community in one way or another, please have a look at http://commons.wikimedia.org/wiki/Category:Highlighted_content_from_Wiki_Loves_Monuments.
Thanks, Tomasz