There was a time I hearted Chitter, the conversations and the connections. Today, Chitter is quite a different proposition as a media channel. It’s ability to allow anyone to have a voice is mediated by their audience. Chitter is free and allows anyone to dive in and grab some attention. Chitter works better for individuals, when they cluster together as a vaguely aligned group who understand and share some common understandings about how to behave. Following the rules, means the cluster expands and so doe the chances of the individual to increase their social-capital – be it neo-capital within the phenomenon.
Of course if you don’t know this, then someone who apparently has connections and followers, posting attractive messages may well appear knowledgeable and influential. To make sure, people produce all sorts of media around their social-presence which reinforces their correctness. But all that glitters is not gold. It is less easy to impress people who demand evidence. For example, while videos about using Minecraft, doing science etc., are interesting, as is posting links to scholarly work — actually showing that what is happening cannot be achieved in another (often simpler) way is more difficult. Showing that what is happening is ‘better’ is ineffable though the media and human filters that regulate the ‘clusters’ correctness (social importance). If this wasn’t’ the case, no one would bother researching or talking about methods of research in attempting to improve education. I reject the idea that ‘social’ is a short-cut or ‘grass-roots’ version of academia. Plenty of people do both.
The clusters tend to focus on particular topics (each node likes to have it’s own operating space). This can have an effect on reality. By appearing to be on the leading edge, it is possible to build social capital and actually climb the ladder. Remember nodes like to bind with other like-nodes in the cluster, which is another form of in-group and out-grouping. The problem I have here is that I want to be convinced by evidence rather than media representations. While it’s great to see people blogging and sharing, it does no harm to look a little deeper than media-presence and ask yourself, is this really golden?
Playable 
I think that a lot of educators using social media tools, especially the ones with the easy entry points, have never really given the concept of networked learning much thought. It is very easy for people to pose as “experts” or to push a particular educational strand because they don’t see the inner workings of the tool as you describe in your post. There are plenty of educators who believe that they “own a PLN” or that someone can be founder of a #hashtagED. From personal experience, it can be very difficult to get a meaningful exchange when pushing against a hot topic – and very easy to rub other participants up the wrong way. (Perhaps my metaphors of wolves amongst the sheep could be what does it!)
The network, accessed by whatever tool, is a constantly changing and impossible-to-pin-down beast. You can spend a lot of time yelling into the gale and not advance your understanding of a concept by one bit. But people like to belong to groups – I constantly think back to Stephen Downes’ work in this area – and those of us who are naturally insecure, skeptical introverts will be an uncomfortable fit. Twitter can start an idea or an exploration but I find it is not that useful for deep thought, analysis and progressing a meaningful discussion.