SPICELMF  http://blog.busymac.com/blog/2008/12/google-caldav-versus-busysync.html

BusySync put up that comparison. I actually don't use BusySync yet but I plan to download the demo now. I was very hyped up about Google's iCal support, then I realized it only pulls your gCal down to iCal. Personally, I use iCal and would like those calendars to be pushed up to gCal. I'd basically have to delete and recreate all my calendars for this to work.

Not to mention for some reason all the calendars are broken up under their each "folder". For example my appointments calendar is under Google:Appointments.. why? Call me OCD but I find it annoying.   
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