I just want to say that I appreciate HP employees filling in on here from time to time, trying to help people out.
I belong to several other forums, notably the Apple discussion forums since my wife is a Mac-head and we own iDevices. For support, I think HP's forums are better, you have actual people on here who try to help out and address peoples' issues whereas Apple's discussion forums are far more austere (arguably lacking) in comparison.
I too participate in the Apple Forums from time to time. As a general observation, Forums are only as good as the participants make them. I've only been here a short while, but its my impression than many users here have unrealistic expectations that HP (the company) will monitor and reply to postings here. As you know that is not the case in the Apple Forums either. Perhaps if the this were renamed to HP Users' Forum there would be less unrealistic expectations.
I know its frustrating to post a message and not receive a reply. But this is really a community of end users so its only reasonable to expect the luck of the draw if someone knowledgeable sees you message while its still fresh and answers. One observation I do have in comparison to the Apple Forums is that there seems to be a higher rate of answers in some areas/topics there. I attribute this to the fact that Apple has many many more topic areas, thus enabling a much more focused user experience. Many of the topic areas in this Forum are much broader in scope by comparison.
I second your positive reaction to having HP employees participating on this Forum. And I am very impressed by what I have seen about experts days on here. I'm looking forward very much to the next one in my current area of interest regarding printers. This is certainly unlike anything I am familiar with on the Apple side, great idea!