In a nutshell, 12c boasts the following major improvements over version 11g:
- More compact file structure. Oracle has rearranged files in installation directory making it easier to find stuff.
- Imaging services are now built in. IPM/Imaging components are now pre-installed in Content Server and there's no need for separate weblogic managed server to run Imaging.
- Trash Bin in Framework Folders. Framework Folders have now been updated to include Trash - a very handy feature!
- Updates in Dynamic Converter. Dynamic Converter is now built into the Content Server and features improvements in template management.
- URM is built in. WebCenter Records is no longer a separate product. All records management features are now included in Oracle Content Server.
- Site Studio is still in. While Oracle Site Studio is bing phased out in favour of new WebCenter Sites, Site Studio component is still included with WebCenter 12c.
- WebUI/ADF UI built in. ADF UI that has debuted in 11g as a standalone WebUI application has not been built in, for a much improved user experience. And if you enable Imaging, it also includes Image Annotations.
- Video Manager is also built in. And if you enable it, you'll see video renditions in ADF UI.
And here's the first of the quick walkthroughs showing you the new, more compact file system of 12c: