Last year, when I flew to Chicago, IL, for Microsoft Ignite, my Gmail inbox had my itinerary neatly collected at it top and the information was effortlessly coordinated with my Google calendar. This year, when I make my travel arrangements, I'll be using the email address associated with my Outlook inbox. This is because Outlook is now displaying your travel arrangements in both your inbox and calendar via "a simplified summary card," i.e. a floating window with the basics of your trip.
The summary cards also include hyperlinks to relevant web pages, so if you need to check in to your Southwest flight (and avoid the dreaded C group), you can do that right within your Outlook inbox or calendar. To help things along, Outlook will also send a check-in reminder 24 hours in advance. And -- showing how Microsoft is integrating other services into Outlook, per remarks made in the Build 2016 keynote -- users also have the option to book an Uber ride off that 24-hour reminder.
What if you don't want your coworkers to see all your travel information via your Outlook calendar? The good news is that the travel events are marked Private by default, so they won't be displayed in the calendar your coworkers see. (Unless, that is, you want them to see that you're flying to Maui, so they can be properly envious.)
Another calendar auto-add? Package delivery notifications. This may come in handy if you're expecting a delivery that must be signed for.
These features are coming to Outlook on the Web and Outlook for Mac users now, provided they have Office 365 subscriptions that include Exchange Online or are users with new or upgraded Outlook.com accounts.
You can turn this feature on or off by clicking the Settings (gear) icon, selecting "Options" and then selecting "Calendar." The settings are in “Events from Email.”