Google Calendar updated for more interactive info
The main two new features are the new options allowing you to initiate calls directly from Google Calendar, and to open an address in Google Maps. This is a nice bit of integration between apps, and should make interacting with calendar events nicer. The update also brings suggestions for locations when you are creating and event, and a quick event creation option from the month view.
As is standard for the Google Calendar found in the Play Store, it requires a device running Android 4.0.3 or higher, so Gingerbread people need not bother. If you want the update, just head over to the Google Play Store.