The author is risking being a bit glib without much more detailed data check. People don't like to pay for stuff, and while surely Twitter has many users for w

The author is risking being a bit glib without much more detailed data check. People don't like to pay for stuff, and while surely Twitter has many users for whom $4 would be irrelevant, it's going to be a surprisingly small number - and - we've already established a price of $0 in people's minds for the service. Charging $25/month for the blue check and a bunch of other pro services (including priority in feeds) might be some kind of opportunity. Where the author is correct and also reasonable in being more generalized about it ... is the lack of a good Ad Program. That should be embarrassing. Twitter has enough data to be able to offer something approaching targeted, actionable Ads like Facebook. And I think they can do it in a reasonable way.