Yes, most any content purchased for use in Studio 10 and 11 will work in Studio 12. This is accomplished using the Content Transfer Wizard. See this FAQ for instructions on how to use the wizard:
If you are using Windows Vista, some content purchased for Studio 10 may require a special procedure to install. Some Studio 10 content discs were originally made for use in Windows XP only. As a result, an error may be reported when installing this content in Windows Vista. The following link takes you to the FAQ on how to install this content:
The Content Transfer Wizard works with Studio 10, 11, and VideoSpin only. This means that any content for Studio 9 and earlier cannot be installed and made available within Studio 12.
There are a few issues that have been identified where certain content may not transfer properly to Studio 12. Click the link below to go to the FAQ on that issue.