There are three clear benefits for advertisers that will arise from this partnership.

Perhaps the biggest is a simple result of the increased scale and reach of the combined offering. With a near-30% market share, campaigns will become easier to scale, long-tail keywords will be easier to monetize and analytics programs will have more data with which to work.

The second big advantage will follow over time as the increased volume of search data available to Microsoft permits them to improve their algorithm and provide better relevance to their users, as well as higher CTRs to advertisers.

Third, there will one less self-serve ad platform to learn, meaning that the barriers to entry for new advertisers on the Microsoft/Yahoo system will be reduced. This is not a small advantage given the numbers of new affiliates, publishers and advertisers coming into the advertising ecosystem right now.