From a naive point of view, it's a massive linear problem to find worth while content on the net. In other words, view every single page and mark web sites as interesting or uninteresting.
So along comes social networks with their tagging, their bubbling, their web 2.0, and their oohs and ahhs. This kind of helps, because viewing every page on the web is just not feasible, so we rely on a cooperative effort to spread out and share what we think is interesting with each other. You end up with sites like "digg":http://www.digg.com and "delicious":http://del.icio.us which employ some sort of social voting to define what's worth your time versus what's not. The problem then is that you get a single inherent "social personality" of the aggregate that is most likely different to your own personality, and therefore you find different stuff interesting. It could be argued that you do narrow the search space by providing some sort of human sorting to the web though. Unfortunately, this is less useful the further you deviate from the mean aggregate personality.
The problem that we need to solve, is how do we find all the stuff on the web that each individual is interested in without having to get everyone to check every single web site, every day, for themselves?
There's "61,332,021":http://www.whois.sc/internet-statistics/ active domains right now, that's a large search space. I cram a lot in to my day, but even that's a bit too much for me to read ;)
On top of this, every one has different interests.
This is a big problem, and it's solution has serious implications for each and every one of us using the Internet.
I don't want to give away too much, but I have an answer. Private beta coming to this blog in the coming months. Stay tuned.
My email if you need to get in touch (throw this in to your command prompt - damn that spam): echo 1l2x@r3t2rs.c4m | tr '12345' 'aeiou'