The Tweet has now been removed but various sites saved and published pictures of an HTC Vive headset with a RealSense powered integrated central 'horn'.
In the snap you can clearly see the central 'horn', which is the Intel RealSense integrated component. Either side of the 'horn' is a set of three cameras opening up lots of useful, accurate sensory information for VR system processing.
The leak came from Dimitri Diakopoulos, is an Intel Prototyping Engineer. He said that the RealSense 'horn' could track hand movement as well as IR-tracked controllers. The camera arrays can scan the environment in real-time. This will help you move around in VR without tripping over the cat.
Chipzilla could eliminate fiddly setups when you use your HMD in different rooms too.