SEPM has a very high maintenance time cost associated to it next to cloud. I've got a small group of Mac OS 10.10 computers and for those clients I've probably spent more time dealing with the software than every other client combined in my organization.
Every time SEPM version increases, the SEPM server has to be uninstalled, and wiped of any software/registry settings etc, before the new client can be installed. Plus it constantly breaks leading to a similar procedure.
If you've not noticed Symantec's website is quite discheveled and that leads one to believe that that's the reason why Symantec.Cloud has yet to be released. Plus Symantec was once more of an industry player that it is now, but they probably don't realize that people are fed up with the lack of attention to the user expierence.