Thanks to the many attendees that came to my presentation "Oracle 12c Parallel Execution New Features" at the DOAG conference 2015. You can download the presentation material here in Powerpoint of PDF format, as well as check the Slideshare upload.
Note that the Powerpoint format adds value in that sense that many of the slides come with additional explanations in the notes section.
If you are interested in more details I recommend visiting this post which links to many other posts describing the different new features in greater depth.
Multi-Version Read Consistency in Oracle
13 hours ago