I'm also having issues with plaxo and icloud. Plaxo syncs "All on my Mac" or "All on my iphone" address books... but not your icloud address books... so you, like I, will end up with address books that are out of sync.
Also, the "synchronize with google" only seems to sync the addresses stored "on my mac" so it too does not sync your icloud contacts.
I've copied all contacts "All on my Mac" to my iCloud account and then deleted them. This deletes everything from Plaxo and Google... but at least now my Apple equipment has all my addresses is in sync.
Plaxo is incompatible with Mountain Lion and iCloud. They intend to concentrate on syncing Windows based equipment and have abandoned development for use on Apple, because really, the iCloud is doing what they offer... with the exception of the Personal Assistant service.... which it seems I can no longer use.
You can choose between plaxo... or iCloud.
BTW... I just managed to sync my iphone (updated by icloud) to google Contacts by adding an exchange account to the iphone (see http://support.google.com/mobile/bin/answer.py?hl=en&answer=138740).
And then sync Plaxo to the Google account.... all my icloud contacts are now on Plaxo.
I think it is important to remember not to close the loop otherwise you end up with duplicates....
So mine goes... Imac (I use icloud address book only) -----> Icloud -------> iphone (I use icloud address book only) ------>Google contacts--------->Plaxo---------->Windows devices.
Any updates in plaxo get fed back through google to my iphone and then to my Macs via icloud.
Here is my situation, I am (unsuccessfully) using plaxo premium and iCloud. Here is my setup:
MacBook with contacts
iPad with contacts and corporate exchange server contacts
iPhone with contacts
Windows PC with outlook
- hotmail (primary email server using my own domain email)
- yahoo mail
The more I try to sync them all together the more mess I seem to make. Could you make a recommendation to me?