I was wondering how the questions on the main page of SO are organized. I've read that the default view is simply a "flat list of the most recent (n) questions sorted by activity date" (link). However, once I set my 'favorites' tags, questions that contain my tags will appear on the home screen in yellow.
How does SO decide how to intersperse my non-tag ("white") questions on the main page? In particular, how does it decide how many of these questions to put on the main page, and how does it decide on the content? Are these 'white' questions simply ordered by recent activity, or is there some sort of LSA done in order to bring me relevant questions that I might be interested in, even if they don't have my tags?
With regard to the 'yellow' questions, are all tags treated equally, or will some tags be preferred if I show a lot more activity in those topic?