Though it would be interesting to have the suburbs (which are actually in conurbation with Brussels) included here as well. When I think of my family there (Vilvoorde / Zaventem/ Sterrebeek area), may aunt's household was obviously bi-lingual (Flemish-German). Two of my cousins married francophone partners, two other Flemish-speakers, but all the marriages ultimately broke up, and my cousins tend to speak Flemish with their children (but also German, when we visit them - they all used to work for longer periods with German companies - so I think that still qualifies as multi-lingual households). I think I have a few years ago seen a map on how Flemish is entering Brussels from the East, would be interesting if that trend goes on.
Btw, just in case you wonder what is driving my interest - my oldest cousin's first marriage broke up because he couldn't stand his father-in-law's Flemish nationalism (with Gross-German undertones) anymore, and what he shared on that with me was quite irritating.
Getting reliable figures for the 'Vlaamse Rand' is the big problem there. The best indicator there are probably municipal election results (since these tend to play out along linguistic lines). But even that still leaves one with a lot of 'noise' (EU-related expats form a non-negligible part of the population of some of these municipalities and in principle are allowed the vote).
For example, based on the 2012 election results, it's safe to say that Linkebeek is about 80% francophone, but just how accurate that 'about' is, is near impossible to say.