A basic one at least.
With the advent of the second gen twitter clients, which support, among other things, groups, users are confronted with higher barriers to entry and exit: In all clients, the painstakingly prepared groups are hardwired in the client. No easy way to get them out. When one desires to switch to a new client, he has to recreate all these groups by handpicking users one by one.
The problem becomes apparent even in the case where one does not necessarily want to change twitter client, but he simply has to work on two different (or more) computers.
In my case, I had to recreate the Tweetdeck groups for my desktop and laptop computers. And I did it only for the two out of four computers I use and for two out of seven operating systems (3 windows, 1 mac, and 3 flavors of linux). I did not even manage to create them as exact copies.
Now, this call might sound like a luxury request, but given the path the twitter clients have taken (check Nambu or AlertThingy or Seesmic Desktop, to mention a few), you will notice that ‘groups’ is one of their prevalent characterists. So dealing with this feature effectively is essential for the success of the product.
And it is very simple really. A CSV or XML file would suffice. With bare minimum information. The name of the group, the twitter account it belongs to and the follower or friend ids that belong to it.
And even if the software vendors do not to go this way for fear of loosing users, there is something else they could do, to allow portability of groups for the same client but different computers: store this piece of info in the cloud. Create a simpe web app where each client will connect to and retrieve the group data.
Some people have already hacked their way to group migration for Tweetdeck but this, clearly, is not the way for the masses. Hence this call. But is anybody listening?