I would argue that these are not the most influential technology companies of our lifetime at all. Google, yes, but what about Microsoft who put a PC on every desktop, or Apple maybe for taking the smartphone that Blackberry had invented and brought it to masses, or IBM for Watson, or Oracle for the Relational Database, or even Wordpress. Google revolutionized the internet, they did to data what MSFT did to computing, but FB and Twitter are essentially the same, one's a photo sharing site, the other wordpress for the twitch generation. What about GPS, hasn't that touched more lives in more meaningful ways that Twitter?