[ljf]

I'd also guess that profitability is not spread evenly across all users, and certainly not across all countries.

I'd guess a good chunk of us are worth £0 (or even negative) and then there is a long tail of increasing valuable users who interact with adverts and services.

Amazing how valuable some of the users must be!

[ramraj07]

Absolutely. The fact that a single ad click for personal injury lawyers could fetch Google hundreds if not thousands of dollars is testamount to this.