Microsoft (NSDQ: MSFT) plans to close the adCenter AnalyticsBeta program, the company said in a post on the adCenter blog. Microsoft said it will still offer technical support to existing testers through Dec. 31, but it will not accept new participants. It didn’t offer a reason why it was winding down the program, saying only that it hoped to understand the needs of small and mid-size self-service customers as well as better develop its analytics strategy. Microsoft, like Yahoo and AOL, has bet heavily on the growth of display advertising the past few years and with the economic downturn, its been struggling. Perhaps a sign that it felt it couldn’t effectively compete: the blog post, written by adCenter exec Mel Carlson, directs users to two dozen other analytics providers, including Google Analytics, Omniture, Yahoo Web Analytics and WebTrends.