The biggest of the independent real-time search engines, OneRiot, restructured its management today and laid off an unknown number of employees, including company co-founder Robert Reich.

Kimbal Musk, a serial entrepreneur who served as chief executive, is stepping aside to serve as chairman and making way for longtime president Tobias Peggs to take the lead.

The Boulder, Colo. company, which raised $27 million in venture capital, has pioneered real-time search, a way of looking for content that’s hot or trending at any given moment. After launching a consumer-facing search engine in the fall of 2008, it pivoted from being a destination site to becoming a real-time ad network after Google entered the field. It now delivers display ads to about 120 different developer partners that show its search results in their products through a program called RiotWise.

The company says it’s now showing 1 billion impressions per month of search ads. Content companies, like ours or The Huffington Post, can use OneRiot’s network to engage in an interesting form of arbitrage — they can buy cost-per-click ads on OneRiot search for less than the value of ads that they display on their home properties. So you’re buying visitors to your website for less than the money you make from their eyeballs once they get there.

The problem is, real-time search ads, don’t have the same CPCs (costs-per-click) that conventional search engines see. For example, Google picks up a lucrative share of product and e-commerce related searches that a real-time search engine is not positioned to get.

So OneRiot needs massive scale to succeed. While impressive, it has much farther to go than a billion impressions a month.