We have had a number of problems using Profile Manager to deploy settings. Wanted to share our workarounds.
If a profile fails to deploy... it appears to erase all of the users profile settings... therefore it's important to test your profile settings first prior to deploying. This appears to be a bug. Logging in and out may refresh the profile... but you must first remove the bad settings.
Be sure to have your firewall ports open for Profile Manager communication: http://support.apple.com/kb/HT5302
Profile Manager May Fail Under the following circumstances:
-- Pushing "Calendar" settings without a user's valid password (even though the field is optional) will cause the profile deployment to fail:
0::Aug 29 16:31:11.766  <10.0.142.201> Status='Error' CommandUUID=0afef3a0-d457-012f-b3e9-406c8fb90eeb
 => Array
[ErrorCode] => -319
[ErrorDomain] => ConfigProfilePluginDomain
[LocalizedDescription] => The 'Calendars Account' payload could not be installed. The account credentials were invalid.
-- Polymorphic profile settings. IE it does not appear to support things like "Multiple Group Restrictions" blending together. In other words... having a user part of a "Base Users" group and a "Sales Group" that have different "Restrictions" will most likely fail. The old MCX profiles seemed to support this, but not Profile manager.
-- Mobility syncing does not appear to work unless "Merge with user's settings" is enabled
-- Unconfirmed... if you restrict a users access to "System Preferences -> Profile" ... the profile updates may not occur.