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Upon closer inspection, I see that piCal does have good support for repeating events -- perhaps even better than PostCalendar. PostCalendar does have repeating events, but the options for setting them is in a much more simplified interface -- I haven't figured out yet whether the piCal repeating events interface actually provides more functionality or not.
What PostCalendear DOES have that none of the others (in any CMS that I have tried so far) is a full set variables for event contact (name, phone, email, website) and location (name, street, city, state/province, postal code) and event fee. This is in addition to the more typical event title and event description.