Microsoft account users were able to chant through Email dashboard by using Google Talk chat protocol and Facebook account. But within couple of week this chat protocol service is discontinuing for some internal issue. Microsoft wants to boost up Skype user then have decided to stop Facebook chat service from their email dashboard. And they want to engage more people to use Skype. Thus people can take advantage of the more robust ways to keep in touch with friends and family.
On the other hand, Google talk is no longer available. Because this service was a biggest failure product of Google. They didn't able to get engage more people with Google talk chatting service and there was not any exceptional service and feature on Google talk. As a result Google announced a new communications product name Hangouts in May 2013. After that Google talk got worse posting on the communication product series.
Though I can't say that Google's new communication product Hangouts is successful. But it seems to me that they are forcing to use this service on Android device but in reality majority of user don't feel comfortable by using Hangouts.
Due to Google's decision Microsoft stop Google talk chat service and for promoting Skype they have decided to discontinue the Facebook chat service also. Microsoft confident that Skype for Outlook.com provides the best experience for chatting and making voice or video calls, right from your inbox, when the conversation warrants richer communication than an email exchange.
However Still I can use Facebook chat on my Microsoft account, but maybe within shortest period of time they will stop this service.