I've just been sent information on the following free online event which covers new ways for Flex Developers to work with PDF documents.
In short, you can build a GUI in Flex to skin the PDF and how the user can access the document contents. The PDF can contain images, text docs, or any Flex/Flash content (such as a video player or game). The Flex navigators are the GUI for how the user accesses the content of the PDF.
There is potential that this will offer new revenue opportunities for Flex developers as agencies and company creative departments often use PDFs to distribute their marketing and promotional materials.

The event details are:

Join the Adobe Acrobat User Community on Wed. November 18, 2009 for a free eSeminar on how to create highly branded, custom PDF Portfolio layouts using Acrobat 9's ActionScript API and Flex. PDF Portfolios let you combine Flash/Flex/ActionScript with PDF to redefine what a document can be. If you are a Flex developer and are interested in leveraging your skills in a new and exciting way, this eSeminar is for you.

Overview
Free 60-min Acrobat 9 PDF Portfolios for Developers eSeminar with live Q&A

Date
Wednesday, November 18, 2009 Time 10-11am US Pacific (1-2pm US Eastern)

Free Registration
http://www.acrobatusers.com/events/1475/pdf-portfolios-developers