Not as involved as I was - due to the fact the team was a lot smaller back when we launched the Xbox 360. That said, I spent a lot of time with Xbox One and write up feedback / suggestions for the dev's/PM's on a regular basis.
Usually I spent an hour or two in the evening at home on my Xbox One checking out the latest build. If I am not on Xbox 360, then I am usually on Xbox One. Or now....'Gaf.
Sony has gotten notoriety for singling out Mark Cerny as the lead architect of the PS4. Why doesn't Microsoft have an equivalent? How big is the team that decides specs and thermal, die size, etc budgets?