This is one of the main features I found lacking in Twitter for ages & I spent ages trying to find 3rd party apps that implemented this well with limited success. I am glad they implemented it and seems I was one of the lucky few to get access to it last week. Trouble is, after creating my lists and telling everyone to go see them, lots of my followers were unable to look at them, simply getting a blank white page with no explanation. I think this was bad planning for the roll-out on Twitter's part. I think really everyone should have been able to see lists up-front, even if they couldn't create them and if not even that, then to have a default go to page explaining that the reason the user can't see the page yet is because it's a limited beta. Beyond this initial gripe, I am a little concerned that this is going to make Twitter's spamming problem worse, by making it easier for the spammers to locate target groups and spam the hell out of them (it won't be long before they've figured out bots that can scrape these lists). Also, this whole idea of how many times you've been "listed", is going to become another one of those Twitter status/boasting symbols that's actually pretty easy to rack up once you have a bunch of bot-run Twitter accounts. I'm still generally positive about this development though, even with the above niggles. - Alex Trup from FriendFeed MT Plugin