Well, stereoscopic gaming is ok, I have a PS3 in the living room hooked up to a 55" 3D TV and it is fine for occasional playing. At least it gets used more for gaming than 3D movies (fargin premium price of 3D blu-rays)
I got a benefit when using it with Hustle Kings (pool game) and I liked the increased immersion in The Fight: Lights out
But stereoscopic gaming is just the beginning, we will really see the benefit next year when proper HMD's come to the market (i.e. Oculus Rift v2) with head tracking.