Introduces Stream Marker in the API

From their Dev Blog:

Today we’re adding support for Stream Markers to the API. This will allows clients to sync where you are in your stream, global, and even in individual threads between clients.

How successful is or will be is an argument best left alone, but I do love that fact that the core team is implementing ideas and features after actively taking feedback from its users and that these very features more or less originated because users felt there was something lacking in the experience Twitter was offering.