Twitter has added the ability to start a direct message directly from a tweet. Each tweet now includes a small DM button that can be clicked to privately share a public post without selecting the "share via DM" option in a tweet's menu. Twitter says Messages is a fast growing part of its service and the network saw a 60% increase in DMs last year.
More tweets are also being shared through DMs and this feature will boost that trend. There was a 200% increase in the number of tweets shared during the second half of 2015.
This button only appears on mobile devices, not the web.