It was a subtle change, so you may not have even noticed it, but now you can send an email from a calendar event. When you click on a calendar event on your Google Calendar, along the top you will see an envelope for email. Once you click on that icon, you will get an email window like the second image. It will automatically add anyone who is invited to that event to the email and you can write up to 2400 characters. It is a great way to ask a quick question or share some brief information with all those who are coming to the event. I've been using it to ask teachers where they would like to meet for appointments
or to remind them about things they will need for our meeting.