In a world where cloud computing is becoming the standard, one could think of 'web-scale' storage architecture as being something of a 'participatory democracy.'
More and more companies are becoming public cloud service providers. Don't think Microsoft Azure or Amazon Web Services. Instead think of somewhat smaller businesses (relatively speaking): gaming websites, online retailers, and other traditional businesses that are using software-as-a-service (SaaS) to deliver new value to customers.
Even these smaller public cloud providers look back wistfully at a time when 'gigabytes' were considered big. For them, even terabyte-scale is fast becoming history. They are looking at managing petabytes of data. And soon more petabytes. And later even more petabytes. You see where this is going.