Notes:

If you use iCal or any program that uses the ical format, you can subscribe to this calendar using the following address:
http://www.google.com/calendar/ical/6rde7u7ats30ajc4oq7850sbrc%40group.calendar.google.com/public/basic.ics

If you use Outlook/Windows, you can subscribe to the calendar by following these instruction and the calendar address
webcal://www.google.com/calendar/ical/6rde7u7ats30ajc4oq7850sbrc%40group.calendar.google.com/public/basic.ics

If that doesn't work for you, try subscribing to the calendar in RSS format:
http://www.google.com/calendar/feeds/6rde7u7ats30ajc4oq7850sbrc%40group.calendar.google.com/public/basic