Today at its Ignite 2019 conference in Orlando, Microsoft announced some improvements to Cortana. One big one is that it can now send you a daily Briefing email. The idea is that it collects the things that you're supposed to do that day, and puts them into an email. This can be based on appointments, commitments that you made in emails, and more.
There's also a new improvement that's meant to make planning meetings easier. When you send an email to someone for a meeting, you can include Cortana on the meeting, and Scheduler will take over. You can tell Cortana the specifics of the meeting in the email, using natural language.
Moreover, it will automatically book a meeting when all participants are available, assuming that you have access to the participants' calendars. The recipients can respond by accepting the meeting, and Cortana will send out calendar invites to everyone.
Microsoft also outlined a few features it has in the works going forward, such as integration in Teams, updates to Cortana on Windows, and more natural conversational interactions. These will all be available in the coming months.