In January we published a spate of research around automation tools specific to the search marketing space. See "Automation Helps Marketers Scale Organic Search" and "The New Paid Search Automation Landscape." Our audience for these reports is the enterprise marketer. So we represented here tools that sell directly to marketers. But, of course, there are vendors who service marketers indirectly — by selling agency-enabling technologies instead.
One such vendor, Canadian-based Acquisio sent me some case studies recently about the efficiencies it brings agencies. Like the vendors we featured in our report (e.g., Adobe Search Center, Marin Software, Kenshoo, Efficient Frontier), Acquisio provides bid optimization, campaign management, and reporting. But Acquisio's sweet spot is providing these services for agencies that might manage high volumes of keyword groups across several search engines for multiple clients. One agency grew its client base by 50% without adding any new headcount by using Acquisio to support campaign workflow, bids, and reporting.
The takeaway here for agency readers is that there are considerable firms outside of the set we profiled in our published research that might provide particular value for you.