I just upgraded to Mountain Lion from Snow Leopard (I think?) and now my iPhone calendar entries will not show up in iCal.
They are not just recurring events, it seems that all iPhone events that were added after this point are not syncing with iCal.
All entries are frozen dating back to the point of upgrade, but the recurring events continue to show up.
To test it out, I subscribed to the US Holidays calendar, and it doesn't show up on my iPhone either.
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