Ever since Twitter announced it is working on a new Lists feature a month ago, users and developers have been awaiting its broad rollout. Over the past few weeks, Twitter has been expanding the number of people in the Lists beta, but now it appears that a full rollout is under way. As of yesterday, Twitter employee Nik Kallen reported that "25% of all users have Lists." And then he Tweeted: "We're releasing lists to even more people.