The main problem I see with that is that there has to be someone who's got a reasonably centrally-located place who's willing to be invaded once a week and who doesn't have cats.

The only reason I've never hosted a brunch, apart from the fact that I'd have to spend a few days scrubbing this place from top to bottom, is that a good quarter of my friends are too allergic to cats to be able to stay for more than a few minutes.