All @names, such as @MacRumors, will no longer count towards the 140-character count, nor will media attachments, retweets, or quoted tweets, but links will still eat up 23 characters.
Twitter declined to comment publicly on The Verge's leaked release date, nor is a source for the launch date given, but the change has been in the works for months. Twitter announced the news early to give its developer partners time to make any needed updates to products using the Twitter API.
Twitter has used a 140-character restriction for each tweet since it launched in 2006. Reports earlier this year suggested the microblogging site was considering eliminating the 140-character limit altogether, but Twitter CEO Jack Dorsey later said the limit will remain in place. Still, Twitter has been exploring ways to allow people to better express themselves and has said it has additional plans to make existing uses easier and enable new ones.