How do I sync android phone contacts to my online gmail acct? - Gmail Help
Specifically the last post of the thread....
Posted by DonutDude:
I had the same problem. In 1.6 using the contacts-> edit sync groups-> Sync all contacts simply does not work.
This was not a problem in cupcake because cupcake had Auto-Sync (which does work) on by default.
THIS PART: To fix your problem go to settings->Data Synchronization and enable Auto-Sync. After a minute or two your online Google contacts will be up to data again.
I just tested it, and it works. Make sure the tick boxes in Auto Sync are ticked. If they are already, then untick them, and tick them once, and the auto-aync will automatically update from that point. Check your online contacts on Gmail, info on Calendar, and emails on Gmail, and things should be sync'd perfectly. Double entries and all...now you can delete any double entries you have manually from Gmail contacts, these changes will be also made to your phone's contacts.
You now also have a back up of your phone's contact info should something terrible, like a child stirring it in a cup of OJ, happen.