Within "the next couple of weeks," Microsoft will discontinue support for Facebook Chat and Google Chat in Outlook.com.

Microsoft notified Outlook.com customers of the pending change via an e-mail message from the Outlook.com team sent on February 24 (Thanks @lindhartsen)

Microsoft attributed the decision to drop Google Chat integration to Google's decision to discontinue the chat protocol used by the Google Talk platform.

A link to the Google decision points to a page noting that Google Hangouts replaces Google Talk and does not support XMPP. XMPP is the open-sourced Extensible Messaging and Presence Protocol, an IETF standard for instant messaging. (XMPP originally was called Jabber.)

On the other hand... How I switched from Gmail to Outlook.com (and how you can too) So long, Gmail, it was nice knowing you. After nearly a decade, I've finally moved my personal email away from Google's service. If you're considering doing the same, here's a step-by-step guide to help you set things up the right way. Read More

There was no reason given for discontinuing Facebook chat integration.

"We understand that this may disappoint some of our customers, but we hope that you'll try Skype for Outlook.com chat, and voice, video calling, so you can take advantage of the more robust ways to keep in touch with friends and family," the e-mail message from the Outlook.com team said.

I've asked Microsoft if the company has any more to say about the reason for the discontinuation of Facebook Chat or Google Chat support -- beyond the desire to push the company's own Skype instant-messaging service.

A spokesperson sent the following statement:

"Most Outlook.com customers already prefer to use Skype when they are chatting and we see this as a great option for anyone impacted by Google's decision to shut down Google Talk and associated APIs, or the recent deprecation of Facebook Chat for Outlook.com."