The search world has been abuzz with Bing. Backed by a $100 million ad spend, Microsoft’s new “Decision Engine” is generating a nice spike in search volume. According to recent data from ComScore , Bing’s share of search volume increased to 12% during the period of June 8-12, a 33% jump from the pre-launch work week of May 25-29. So there’s definitely a curiosity factor with Bing. And my SEO colleagues have already given their review  of the new interface and how the organic search results compare to Google. But what will Microsoft’s huge investment in Bing mean for advertisers? Virtually all of The Search Agency 's SEM clients already include Microsoft in their paid search portfolio. So we conducted an analysis of a cross-section of accounts, comparing their performance for the last three weeks of Live Search to their first three weeks with Bing. The initial results have certainly been positive both for both Microsoft and our advertisers: Click Through Rate (CTR) up 15% Conversions up 6% Conversion rate up 18% Cost per Acquisition (CPA) down 3% Although Bing’s search volume has increased on the heels of their aggressive advertising campaign, Microsoft has been more selective on which ads they serve on each search results page, often times electing not to serve any ads at all. As a result, we saw a 22% drop in total impressions. But Bing has significantly increased the relevancy of those impressions, yielding double digit growth in CTR and conversion rate. We will be monitoring this data over the coming weeks to see if Bing can maintain this growth in search volume and conversion rates. It’s entirely possible that this improved performance could represent the “curiosity factor” -- explorers clicking on all sorts of listings to see how the new engine performs. Either way, these early results do suggest some great opportunities for advertisers to obtain higher-converting search traffic with Bing. What type of results are you seeing from your accounts? How have your account management strategies changed since the launch of Bing?