Some good comments on product management from former colleague Cadman Chui over at Red Canary. From some followup comments by Cadman:
I believe Product Management should reside neither in Marketing, or Development. If a product manager falls under marketing, they end up being biased into doing a lot of communications style work. If a product manager falls under development, many times they end up project managing release schedules at too much of a tactical level.
I think most readers of this blog would agree.