Web Science
There is a call from Sir Tim Berners-Lee and Wendy Hall for an academic discipline which studies the internet.
Although this may focus on the internet and its success stories by incorporating lessons learnt in computer and social sciences, I would hope it also draws heavily on work done in the past few decades in the natural sciences, given that pretty much every interesting system studied these days produces knowledge on complex networks. Web Science could be a real destination for generalists!
Social Semantic Web
Glad to see people thinking about the crossover between social networking and the semantic web. It will be interesting to see the spread of papers at the Stanford University symposium.
Novelty Engine
According to Nicholas Carr internet technology is bombarding us with so much information we are all rapidly losing our attention span. This not only forces us to speed-read everything but it prevents us from contemplating the deeper issues. One reason social network tools like Digg, Twitter etc help is because we trust others to read and 
filter on our behalf. However there is still so much to sift through for the knowledge nuggets.
What if we were also able to trust technology to do the reading and filtering? We are already seeing micro-blogging bots at the broadcast end. Social web browsers would also benefit from some intelligence, enabling messages to be organised and filtered on receipt. Again, perhaps the focus would be on identifying posts which are “related but novel”. Or at least routing them into personalised semantic buckets. Are there tools already out there, eg how much of this can you do with Flock? What would it take for us to build trust in personalised blog-reading bots?
Contextual analytics and profiling for emergent collaboration in innovation networks. Complexity theory, social networking and artificial intelligence.
Mpagah 
What it would take is for blogs to be written in a new picture-concept language. Everyone would have to learn and use this language instead of English. A picture or animation akin to a thought language element or dream element(word) would be one level listed in a learning dictionary. Once the language was learned step-by-step as a child learns a language, a picture or animation dense in meaning would trigger a complete thought. A collection of these dense “words” would compose “essays” on the blogs. The standardization of core concepts that would each be assigned to a “word” would make for a quick and dense essay. A “classic” ten page essay on a settled subject constitutes and would be assigned a single “word” just as an observed event is a singular experience dense in meaning, absorbed quickly, but very long in explaining at the learning level — if it is standardized,it doesn’t need to be explained each time: the expanded version is for learning; the compact version is for those literate in the thought language. The essay is one level of explanation in a learning dictionary entry for one word. For more complicated concepts, a movie is an entry in a learning dictionary for a single “word”. Blog reading could not be done efficiently in English.