Microsoft is creating a new Outlook client app, which will utilize the existing Outlook for Web software. The new project is codenamed Monarch, and it follows Microsoft's "One Outlook" vision.
Microsoft is currently working on a new user interface for the Outlook desktop app. The change is coming to Office 2019, which is in development as of this writing. Microsoft is trying to give the app a modern, extremely simplified look with less features in the UI compared to what previous versions of Outlook have.
Microsoft has started rolling out an update for Outlook Mail and Calendar apps for Windows Insider Program fast ring members on Windows 10. The new update, version 17.8241.40785.0, contains the usual bug fixes and improvements but also introduces a meeting scheduling feature.
Few days ago, Microsoft enabled the IMAP protocol for Outlook.com accounts. This is definitely good news for all users of alternative email clients, such as Mozilla Thunderbird. Access to a mailbox via the IMAP protocol provides several benefits over POP3, which was the only option available for Outlook.com/Hotmail users previously, if they did not use Microsoft's Live Mail application. With IMAP, you are able to access all the folders on your server. Also, IMAP saves the "read/unread" state for all your messages as well as the complete list of your messages which is accessible through all instances of your email clients, even across multiple devices.
So, here are the instructions on how to configure IMAP in the Thunderbird email application.