OMA 15 has just been released, the new features are explained in the What's new document and in the video below.
After the release of OMA 14 we hosted two webinar sessions, you can watch the recordings here:
OMA 14 webinar: what's new & conversion
Get an update on all the new (conversion) features in OMA 14
OMA 14 general overview & what's new
Get a general overview of OMA and all the new (conversion) features in OMA 14