I often have to travel from the far west and north westerly ends of
the Picc. and Met. lines to the far reaches of East London and usually
change from underground to London Overground at either West Hampstead
or Finchley Rd for Finchley Road and Frognal. I've done a search on
the TFL site for my particular journey and it now seems that Kilburn
(Underground) / Brondesbury (London Overground) is also a valid out of
station interchange. I've not seen it on any lists and would like to
know if this is indeed the case.

cheers,
UC