We have had plenty of feedback on the usability of our calendar. Based on your requests (and our testing) we have changed the way you view the details of appointments. You now can click on an appointment to bring up the details that previously would appear if you hovered over the appointment.
We think this makes a lot of sense and is how we should have done it from the start. I know it will take a bit of getting used to for those of you quite familiar with the existing behaviour, but we are confident it is short term pain for long term gain in getting used to it again.