Well, here goes some thoughts on what could be very useful in new calendar: Cribbing a bit from my favorite
Online Calendar. Group ViewsThe most important feature of all.
Security based group views into ONE calendar.
Idea would be to have multiple groups be able to post their events into one calendar (analogy would be multiple departments in one company).
The events show up as different colors
See exmampleButtons or drop-down allows selection of ALL groups (visible to this user's security rights), or just ONE group.
Colors help distinguish views when you show ALL
Users with no rights to a group never see events for that group
(Security wise very much in the vein of current Forums plug-in, which you can assign View/Post rights to a specific group and hide from others.)
Multi-view, multi-formatViews: daily, weekly, monthly, yearly, Go to Date
Formats: calendar, list, print view (no wrapper)
SearchIntegrate calendar content into search function of GL.
Account for security as mentioned above.
Recurring eventsevents that occur once a month, every other week on Tuesday and Thursday, or the last Thursday of each month. calendarInfusion supports a wide variety of recurrence rule possibilities!
Email notificationsevent reminders allow users to be notified of their favorite events.