Is there a way to sync Google Calendar with iCal without CalDAV or EAS?
I just thought I would add to this question, given that it was posted in March, with no further activity. Google originally posted this to the Google Blog:


  CalDAV API will become available for whitelisted developers, and will be shut down for other developers on September 16, 2013. Most developers’ use cases are handled well by Google Calendar API, which we recommend using instead. If you’re a developer and the Calendar API won’t work for you, please fill out this form to tell us about your use case and request access to whitelisted-only CalDAV API.


Shortly thereafter, they added this:


  We worked with the developers who provide 98 percent of our current CalDAV traffic to assure access to the CalDAV API, which means many popular products will not be impacted. We remain committed to supporting open protocols like CalDAV. 


As I've heard nothing to lead me to believe otherwise, I presume the current state of things at Google is to continue to support CalDAV. Of course, as with anything else, this could change.