Before that on FF i had an add on that disabled autorun for flash also (very similar to how chrome does it with plugins gotta right click to load it).
But if Google does it only for none Google adnetworks that's going to be a huge lawsuit. The article doesn't really clarify why would it work on Google own networks because they convert to HTML5 or because they will white list their own stuff.
TBH we could've gotten rid of Flash years ago, Google was actually a big supporter for Flash, it was very important for them at some point in time, Google Chat, Gmail Extensions, Google Wave, and most importantly getting high bit rate video on YouTube off the ground (DXVA, OpenGL support was critical for YouTube and every other streaming site out-there), and heck Google promoted Flash on Android until JB as their big gotcha over Apple..