As an important comparison, Facebook just posted 2B monthly actives in Q2. From an advertising industry standpoint, the space has quickly become consolidated s

As an important comparison, Facebook just posted 2B monthly actives in Q2. From an advertising industry standpoint, the space has quickly become consolidated such that Google and FB own the vast majority of ad inventory in the market. Advertisers, particularly large advertisers who contribute a substantial portion of this revenue. As a buyer, I can state from a position of experience that managing an ad buy at scale is just as important as potential performance. If I'm an agency for example, and I can reach massively more people on FB than Twitter, I'm likely going to focus my efforts there even if ROI may suffer from diminishing returns to some extent. A big part of the reason for that is it would take significantly more hours to setup, manage and report on Twitter (or any other ad platform) separately than it would to just focus on FB in that case. So from a business level, the overhead of managing multiple ad platforms can often be a critical deciding factor in addition to just the actual ad performance. Time is money, and lots of people hours cost lots of money, particularly those people who have the technical specialization to effectively manage digital media campaigns at scale. All of that is to explain why total ad spend is increasingly consolidating around FB and Google. And that is REALLY bad news for Twitter from an investor standpoint because it puts a big cap on their growth potential.