I believe what they're describing is basically subscribing to a one-way CalDAV feed. I been using Spanning Sync for two way sync with my Google Calendar with iCal for several years and have been really happy with it. I tried a ton of free/low cost solutions that totally messed up my calendar before just biting the bullet. From that end, make certain you make a backup before trying much.
FWIW, I also sync my Address Book with my Google Contacts, but I use Address Book's sync feature instead of Spanning Sync's (Apple's version seems to work better).