One of the things I discovered at drupa was that there might be videos later about the JDF features in Acrobat 9. So far nothing can be found, but maybe later.
I still think of PDF as an extension of Postscript so that a connection with print is seldom far away. Maybe this release is more of a way to introduce Flash content but I still think that "knowledge workers" need to order print once in a while so they might as well realise that Acrobat includes a mass of pre-press capability. This includes starting off at least the intent of a JDF ticket, the standard for automating print production. It can also be used for the print service provider to communicate requirements on how the PDF should be created.
My impression with the release of 8 was that Adobe did almost nothing to promote this feature. Maybe it is down to print service providers to mention it more often. In 9 the main development seems to be that the JDF content can be exported as html so is easier to access.
With 9, the meetings
explaining new features are organised by Certitec and the speaker is Jon Bessant. 21st August in London and 27th in Cardiff. One session in the morning, one in the afternoon - both much the same. Starting with collaboration in Microsoft Office, new services in Acrobat.com, forms design - in other words all the office features for "knowledge workers", situations where PDF on screen might remove the need for paper altogether. The Flash inside PDF as if there was not enough Flash online anyway, and how to create a portfolio that wraps your PDF in Flash and forces your friends to upgrade to 9. Just before the news on ISO standards there is just time for publishing and prepress.
This might be your chance to ask about JDF. Jon Bessant used to work in support for a print service provider coping with the occasional technical issue caused by the way that PDF files are sometimes originated. So it may be possible to lead him on to a discussion of potential benefits from a JDF workflow. But this may not be in the original script to any great extent. So if you do plan to be there it could be worth a bit of study and working out what you would like to hear explained. I could be way wrong of course on what people are interested in. I just notice that JDF, although not a new feature, is no better understood now that before the previous release.