I don't think it helps at all, maybe a little bit of publicity but I think if that is your goal, you may be better served to place efforts elsewhere. I would wager posting on HN has better odds of landing you a job due to exposure than Stack Overflow. In the end networking is the golden rule for finding employment. HN or Stack Overflow can be used to that end, you just have to remember to foster relationships in the community. Doing so will pay far more dividends that pure knowledge displays.