Contacts in Mountain Lion won't sync to iCloud. iCloud is on for Contacts, the Groups list appears under 'iCloud', but the little wheel keeps spinning, and nothing syncs. iPhone and iCloud work together just fine, but groups and addresses I add on my MBP don't make it up to iCloud. A cursory look at the log reveals some kind of CardDAV error, but several attempts at turning off iCloud, clearing caches, trashing plist files, etc. and turning iCloud back on in hope for a merge option have yielded nothing. It seems that whatever server address my Mac has for my iCloud is wrong, and so far, nothing has been able to correct it. (Side note: before upgrading my MBP to Mountain Lion, I switched my MobileMe/iCloud sync account from my me.com Apple ID, to the Apple ID I've been using forever for my iTunes account, so I can use a single Apple ID going forward. Note that the switch presented no problem for iCloud and my iPhone) Anyone out there with an idea what file/setting may hold the key to this problem?