There is always a tension between 'give me more' and 'give me less' in any information service. At the beginning you want to expand your realm; later you want to constrain it - to find the interesting bits.
People make the best filters - a key thing I keep going back to is how good our brains are at associating trust with people, and having their photos next to the information calls that trust code in our brains. We all look at a lot of thinsg and pass on a few; we all see different subsets of the web; together we sieve it for meaning and interest and pass it on to each other. We've done this with blogs for years, and now we do it with twitter and all the other services shown off at defrag.

The point of the open social web standards I was advocating at Defrag is that by putting this information in common forms, and having clear ways to share it both publicly and selectively, we can apply our existing social filters, and make it easier for new applications that make more sense of these flows of information to be developed without having to be bound to multiple companies different formats and policies.