Eric Wilfrid, General Manager of Microsoft’s Macintosh Business Unit, has posted a blog entry in which he reveals that a Beta of the next version of Microsoft Messenger for Mac, which was originally slated for release by the end of 2009, won’t be available until next March. He wrote: “Progress has been slower than expected due to the challenge of connecting to the most current A/V [audio/visual] code running on the Windows Live servers.”

That update to the instant messaging software will include support for audio and video chats, something that has been available in Apple’s iChat application for the past few years. The last update to Messenger released for the Mac was version 7.0.2, which came out this past February

Mr. Wilfrid also said that the next version of Office for Mac is expected to be released this time next year. As previously revealed, it will drop Entourage in favor of Outlook for Mac as its email client. He said the Mac BU will be at Macworld Expo in February, so presumably more information about Office for Mac 2010 will be unveiled then.

Thanks to Macworld for the heads-up.