Announced early last month, the Twitter profile update will soon be required for everyone on the service. Beginning May 28, all Twitter users will have the new profile, which has already been rolled out to new users and some existing users in the past month.
It's unclear how many people currently have the new profile, which features larger profile and header images, new timeline views and the ability to pin a tweet to the top of a profile page. Twitter did not immediately respond to Mashable's request for comment, but based on Twitter reaction to the design change, it appears that a number of users are still using the old layout (and aren't happy about the impending switch).