Nobody believed mobile would be the fastest growing segment of tech
I disagree about this one. In 2007:
+ AdMob raised $15M for their Series B from Accel and Sequoia.
+ Google announced their Android platform (after having purchased it in 2005).
+ Apple launches the iPhone.
I would say those are major examples of the big bets large corporations and investors were placing on mobile being a fast, if not the fastest growing segment of tech.