The company has said that ads targeted at logged-out users - or people who view tweets without a Twitter account - would bring in $2.50 in average revenue per u

The company has said that ads targeted at logged-out users - or people who view tweets without a Twitter account - would bring in $2.50 in average revenue per user (ARPU). Its logged-in user base brings in more than $4 in ARPU. What's the time scale? $2.50 per user per year seems high. Per lifetime, it seems low.