I think they're overselling it, but Unreal is fairly heavily being used in the early parts of pipelines at various studios, certainly more than Unity engine itself...
i.e. MPC had significant use of Unreal on set for mocap, Framestore has Unreal setup for previs and mocap (they hired some ex-games devs with Unreal experience to work on it)
ILM stagecraft is the 'hero' example (and as mentioned, they've got Helios now), but various studios are experimenting with it in various departments.
Disclaimer: I work for Weta, and above doesn't reflect anything about Weta (Gazebo, etc), it's all from friends/ex-colleagues at other studios...
