Hey thanks for the great question
BlueBird lets us use Promises which basically just makes our code much cleaner and easier to write, It could have been used more extensively in the tutorial but near the end I just wanted to pump it out as quickly as I could.
Lodash also just makes things easier to work with, it has some helpers for arrays, numbers, objects, strings, etc.
RE: [Steem] - Building your own Steem App like "steem.cool" Quickly, and understanding how you did it!