Gatner (they appear to be busy don't they!) states that the number of blogs will peak at 100 million (widely reported, but see BBC summary). It states that 200 million people have already stopped writing their blogs.
So Gartner sees a ceiling approaching. I disagree - I think we'll see an increasing number of people posting online (and not only via the internet, but mobile-based too), but 'blogging', in its current format, implies a continuous stream of thought, expressed freely to all.
But sharing of thoughts and ideas, images and video is both:
- directed (ie to particular people) and
- fractured (starts, may last a short period of time and then naturally dies, possibly starts again)