Twitter has implemented a small change today, which by comparison to Retweets and UI redesigns isn't such a huge deal but it's definitely worth mention. Twitter's prompting question above the box from which you Tweet from has been "What are you doing" since the microblogging platform launched. Today, it's been changed to "What's Happening." It's a wise move because "What are you doing" seemed too narrow for the platform. Broadening the question to match all the things people use twitter for was necessary. Considering that Twitter is now used for breaking news, that term doesn't really cover it. Here's the full text of co-founder Biz Stone's blog post: