Meetings are meetings with guest lists and status.
This will also work for Zimbra calendaring to Google and Meeting Maker to Google.
We are still working on a few parts of this, but it is now basically completely functional and in two test sites.
One other thing. If you wanted to take all your calendar data from something called Microsoft Exchange and migrate it full-state into Google Calendar, that can be arranged.
June 12: In response to queries. This is all SERVER-SIDE to server-side with no end-user / client-side intervention.