This effervescence reminds me of the days gone by when the internet stocks were trading at stratospheric P/Es and were yet to show a single penny in profit for the investors.
Even earlier, the same was the case with the advent of the home computer and earlier, with the car industry at the beginning of the 20th century.
For its hundreds of millions in funding, Airbnb is still underwater and projections are just lines in the sand. The shift in the paradigm of house use for commercial purposes will certainly lift many boats but it is still to be seen which one will float!