Well, finally, many more of us now have access to the new Twitter List feature (think Groups) that many "special" people on Twitter have been bragging about for the past couple of weeks.
Indeed it s a cool, and needed feature, although I'm wondering where the heck has it been all this time?? Many add-on Twitter apps (TweetDeck, Seesmic etc...) have supported group functionality for a long time now enabling you to categorize people you follow into a logical group structure.
So, now what? If you haven't seen it yet (or maybe still don't have access) you'll know when you do. Once you login via web client (twitter.com) you'll notice a huge message asking if you want to create a new list. From then on its pretty simple.
I've started by browsing people I follow and slowly, individually, selecting the people that I'm really interested in and adding them into lists that I've created (some based on discipline, some geography etc...). For example, I have a liss called "ESRI" where I group anyone that is associated with ESRI in some capacity. A nice feature is the ability to share you lists - see my ESRI list (Still young) at http://twitter.com/gletham/esri - as you can tell, naming is important and is used in the url structure). You'll then notice that now when you visit the homepage of someone on Twitter that you've placed in a list - like @ESRI for example, a message should appear that displays to you which of your list(s) they are in. Look at the right side-bar of a followers homepage and you should be able to see all the lists that a person has created.
That's really about it! I guess for now, browsing and sharing lists is a very handy way to search and follow people on Twitter as you are essentially piggy-backing off other people's suggestions.. in a way, its sort of like getting the VIP treatment! Something very cool is that someone can be on a list that you create yet you don't have to be following them.
Lists can be made public or private so if need be you can create a special list of really special Tweeple and keep it all to yourself, although keep in mind, Twitter is about sharing! For simple PC access I use Power Twitter in a firefox browser. I haven't been able to tell which or if I'm on any lists although I have found a simple way to see what lists you have been added to. There's a fine mobile Twitter client called Dabr (see http://dabr.co.uk) access the site, login to your twitter account and select Lists from the top navigation. There you'll be able to see all the lists you've created as well as lists that people have included you on... nice!
Lists on mobile Twitter client Dabr
List building is a slow and tedeous process but over time these lists should evolve nicely and become very useful for searching out people. Please remember if you start your own GIS or GISnews list to add @GISuser and @gletham