Little Bird is an interesting tool. It's in private beta at the moment, but if you register you get a temporary password/user name so that you take a poke around. It's still very tiny at the moment, but it shows a lot of promise.
The first thing that you see in the site are sets reports in different areas, such as beer, wine, food and librarians interestingly enough. So naturally that's where I went. You are presented with a list of the top 500 experts, which seems to be defined by which librarians are most followed by 'insiders', which appears to be something of a self referential group. LibraryJournal for example comes top of the list as its followed by over 1,000 'insiders'. Then there is a listing of new accounts, but followed by insiders, 'listeners' which are people who are following insiders, the most followed insiders, the oldest and the most active accounts. It's worth spending some time wading through this information, since it does give you a good feel for who is who on Twitter - as defined by the other people who Little Bird thinks are important.
There's a very helpful section on what the insiders are sharing. This is a news curation tool which pulls link content directly onto the page so that you can read it there, rather than having to wander all over the web following up links. Next up is a 'comparison' option, to compare other individuals against 'the experts'. This tells you how many experts your victim is following, how many s/he is being followed by, which experts most recently followed that person, and which experts first followed that person.
There is a 'blogs' option - top blogs by inbound links, with listings on most recent posts. Finally, there is a search option which is powered by Blekko, and pulls up websites.
The main flaw - if there is one, is how the 'insiders' are defined. If you don't have the word 'library' or 'librarian' in your biography, then you don't stand any chance of being in the list. The more followers you have, the higher up the listing you go. So if Lady Gaga suddenly put librarian into her biography, she'd zoom to the top of the list, slanting the rest of the content. I think Little Bird needs to have another way of working this out, because it's an easy system to game if you are minded to. However, to be fair, looking at the librarians list, there weren't that many that I would have objected to, but I still find the WeFollow resource a good one to use.
This is another example of the way that the internet - specifically search and authority is now moving, which is towards the individual, and away from the website or the organisation. We're only going to see more of this happening in the future, and Little Bird is just an early example of where we're going to be going in the next few years.