Now Kawai has it in their top pianos. AFAIK Yamaha has never used it. It's not really that nice of a think, in my opinion. I wouldn't pay any extra for it, personally.
Escapement/let-off was introduced in Kawai's previous generation actions, but reserved for the higher specification models.
However, now it is a standard feature of all the current generation actions (GF, RM3 Grand II, and RHII).