well its not hard to sync with google calendars. all you have to do is go to prefrences in ical and add your gmail to it. and sync everything with google. that should do the trick
if you go into ical then click file at the top of the screen then click export for which calendar you want. After that go into your google calendar online and import...that is the simplest way I have found so far...if anyone else has an easier way please let me know
My recommendation is to try SpanningSync. I use iCal on my MBP as well. SpanningSync allows sync from ical to google (once you've also configured gmail in ical like referenced above), and from google back to ical.