Another patent has came to light recently that hints to the addition of hardware V-Sync to their next console.
The patent does provide a little insight though, and makes mention of something called "vertical blanking." What this does is fill in missing frames whenever the game drops frames, kind of like a safety net.
While consoles only had software V-Sync in the past, this patent about a hardware form looks interesting, despite the technology being readily available on PC for quite a while. Who knows if this patent ever gets applied to a console considering their limitations. But it should be interesting nonetheless.