Since today's Oculus update, the correctly oriented image is green, while a strangely-moving, rotated, magenta copy shows up for the right eye only. In other words, the red and blue channels appear to have flipped orientation.
I have just confirmed that it is a rotation, not a simple switch of coordinates; the magenta image is actually not mirrored.
This is true in Oculus Home and the apps it launches. It is also true in gz3doom, and in Doom 3 BFG VR; menus and gameplay all show the problem.