You can publish any of the out of the box IaaS services (full clones, linked clones, SCCM, UCS, Cloud, etc.) and any workflow you can make in orchestrator. So the question really becomes what can you make with orchestrator vs what you can make with service now. You could also theoretically use vCAC to execute a service in service now. The other thing to consider is the permissions model of vCAC with Service now to make sure you can entitle the right services to the correct sets of users. If you have a specific task in mind we might be able to give you more help.
