3) The above rule is quite simple. 90% of consumers will passively engage in the product through consumption (such as playing a video game). They might lurk on forums or read articles. 9% of these people will take it a step further and actively engage in discussions and talk. These are the people that you rely on for WOM sales (word of mouth). They'll "like" a post on Facebook, share it to their wall, reply to a forum thread, RT or reply to something on Twitter. Then you have people who take it one step further and create content based on the original product. These are your fan artists, cosplayers, and even as simple as someone who starts a forum thread or makes a youtube video.
3A) An example I gave of this on Twitter is 3 products that I enjoy: Dominos pizza, the television show The Venture Brothers, and the Mass Effect Franchise. While I spend an embarrassing amount of money on Dominos every month, I don't discuss my purchase online with my friends. I haven't "Liked" their page on Facebook and I'm not a member of their community. I'm still an important consumer and I vote with my wallet. However I'm in that 90% that Dominos is constantly trying to engage with pizza ordering widgets to share on my Facebook wall etc. But I'm not biting. On the other hand, I'm a much more vocal consumer of the Venture Brothers. I'm in the 9% there. I've been a member of several fan sites, tuned into their livestreams and donated money during their charity drives, I tweet quotes from the show and am involved in discussions with other fans I met online. And finally, long before I worked for BioWare, I was in the 1% of this community. Even though I didn't go on the forums much (other than lurk), I created costumes, spread my love of their games at conventions, actively participated in their facebook initiatives etc.
3B) This doesn't just apply to people who like something. This applies to consumption as a whole. The 9% vocal minority isn't a bunch of naysayers. It's literally just the vocal bunch out of the entire group. It includes people who like, dislike, and are neutral. The media has just latched onto "vocal minority" as if it's a bad thing. It's not. It's just the way consumption works. Go look at any Facebook page, specifically their "People Talking About This" (PTAT). We consider 10% a great number. 20% is off the charts. But it rarely goes above that. It's just the way things work.