Comment by tomkarlo

Nice writeup.. one thing I'd add is that usually when companies are given 100 P/E type valuations, it's because everyone's assuming they have lots of growth in front of them. FB is already a dominant player that pretty much _everyone_ in developed countries is either using or has decided not to use. Is there really a scenario in which one sees the usage doubling or tripling down the road? It seems like you'd need to believe that to support a 100 P/E and ~20x sales kind of valuation. 30B or so seems like a much more viable level.