Matthew Yglesias @mattyglesias
Facebook maybe. But Twitter is used by about 22 percent of Americans and has fewer than 300 million non-US users. What’s it a monopoly of? — PolitiTweet.org
Branko Milanovic @BrankoMilan
Twitter and Facebook are indeed natural monopolies b/c their "value" to us increases w/ the number of users. So hav… https://t.co/yeFTnolsq4