Calendar enhancements (these are all within the event details display)

1) mini-calendar preview - the bottom left panel becomes a preview pane of your calendar with the ability to review the day or the week.  The preview only shows the calendar events for the calendar selected (ie - you will not see other calendar layers in the preview).  If you've added multiple guests, their calendars will display in the day view side by side and in the week view as colored blocks corresponding to the guest.

2) drag and drop in preview - simply grabbing the event within the preview allows dragging to a new time period as well as extending/shortening the amount of time - the when information will update automatically.

3) show/hide guests - after adding guests, it is easy to select which will show or be hidden in the mini-calendar preview by clicking on their name - by default they show.

4) add rooms - this should probably be titled add resources - if the domain is a premier or education version, the user can select a resource for the meeting - the resource can only be setup in the domain administration panel.

What's interesting about these new calendar enhancements is that you can turn them on/off from within the event details display instead of through the beta labs function.  Not sure if this is going to be a Google trend or not - previously, all new features in beta would go through the labs settings.

In addition to the above functional enhancements, Google has added some new keyboard controls.  Keyboard controls need to be turned on in the Settings --> Enable keyboard shortcuts.  It's easy to see a list of shortcuts - simply select the ? key when viewing the calendar.