@jeffjarvis As an academic who deals with students and colleagues from a wide range of cultures, faiths, and background, I've found Google Calendar's (previous) inclusion of such a wide range of events, holidays, and observances to be invaluable. Among other things, it allowed me to be more careful about avoiding conflicts I wouldn't otherwise know about when scheduling events and meetings.
Of course, making it harder to be respectful of other cultures seems to be the main goal here.