Larry at Spanning Sync here. As you've heard, iCloud is available to the world as of today. If you've moved to iCloud (or plan to) and also use Spanning Sync, you'll want to be aware of a few things.
Upgrading to iCloud is similar to the issue of upgrading MobileMe calendars which was a big topic of discussion back when Apple started moving MobileMe customers in that direction. iCloud calendars are represented as CalDAV calendars on the Mac. Apple simply doesn't allow syncing to CalDAV calendars. It's not a choice that we've made not to support it or fix it, Apple just prevents developers from doing it.
That said, you can still sync with Spanning Sync even after moving to iCloud. What you can't do is sync the same calendar to iCloud as you sync to Google. The important thing to understand is that Spanning Sync can only fully sync iCal calendars that are "On My Mac", aka local calendars. To make a new local calendar, you can always do File > New Calendar > On My Mac from iCal.
The iCloud migration most likely changed your existing local iCal calendars to CalDAV calendars, but you can change them back. To do so:
- Open iCal
- Click the Calendars button (top left corner of the leathery toolbar)
- Right-click a calendar on iCloud that you want to make local, select Export, and save the export to your desktop
- Create a new calendar "On My Mac"
- Select File > Import and select the exported calendar on your desktop, then import it to the local calendar you just created
- Examine the new calendar to make sure everything is there. There will appear to be a bunch of duplicates because the iCloud calendar is still displayed. Uncheck the iCloud calendar to get it out of the way. When you're satisfied that the calendar imported correctly, delete the iCloud version. You don't want duplicate calendars sitting around in iCal because the duplicates can confuse the syncing system.
- Open the Spanning Sync pref pane and pair up the new iCal calendar, then sync.
Similarly with contacts, iCloud most likely moved all of your local contacts to the cloud. Technically, iCloud hosts these contacts on a CardDAV server which is similar to CalDAV. And like CalDAV, Apple doesn't allow developers to sync to the CardDAV server. The twist here is that syncing to and from Google will continue to happen after moving to iCloud, and all the contacts that are now "missing" from your Mac will be synced from Google. Since these contacts were moved to iCloud, you're now going to see two of each contact in Address Book: one from iCloud and one "On My Mac", aka locally. Obviously, you don't want duplicates.
The solution: If you want to sync contacts with iCloud then turn Spanning Sync contact syncing off and delete all of the contacts "On My Mac". (Be sure to turn off Spanning Sync contact FIRST. If you don't then they might get deleted from Google.) If you want to sync contacts with Spanning Sync and not iCloud, then open the iCloud pref pane, uncheck Contacts, and select the Keep Contacts option.
UPDATE: A Spanning Sync user asked us if it's possible to sync iCloud-based calendars and contacts "one-way" to Google. The answer is yes for calendars but no for contacts. While Apple's sync system is happy to inform Spanning Sync about changes to iCloud calendars, it doesn't tell us anything about changes to iCloud contacts.