Part 3: Sync Your Main gCal with iCal - SOURCE: http://www.google.com/support/calendar/bin/answer.py?answer=99358#ical
1. Open Apple iCal, go to Preferences and then the Accounts tab.
2. Click on the + button to add an account.
3. Under Account Information, enter your Google Account username and password.
4. Under Server Options, add the following URL:
Replace 'email@example.com' with your Google Account username.
5. Click Add and under the Account Information tab, set calendars to refresh every minute
6. In the Delegation tab, you will see all the calendars you have access to, or share through gCal.
7. *Select only those that do not already appear in your iCal side panel. * - That is what I did instead of what Google suggests