My email and calendar sync everywhere. Woot! OS X Address Book, however, completely fails to sync to Google. There's a checkbox in Preferences for "Synchronize with Google" that appears to work, but every time I quit Address Book and restart it, that box is no longer checked.
OS X 10.6.4 MacBook, OS X 10.6.4 Mac mini
Mail, Address Book, iCal
Mail + Contacts, Calendar
HTC Evo 4G (Android 2.1) mobile phone
Mail, People, Calendar
Apparently lots of people spend years fighting this stuff, or spend $100/year for Apple MobileMe. I prefer just giving up on Address Book, satisfied that almost everything Just Works.
Update: Sheesh. OK, so the sync does work even without MobileMe if you work your butt off every time. e.g.: (1) Change a contact in Address Book. (2) Open Preferences, check the "Sync with Google" checkbox (yes, you have to do this every time you open Address Book. Somehow it remembers your username and password though) (3) Right click the MobileMe sync in the top menu bar. "Sync now". (4) Log out of Google Mail. (5) Log back into Google Mail. Done -- your contact change is in Google.