look whom I found on youtube: https://www.youtube.com/watch?v=g-QcU9B4qMc
This presentation by Bruno Lowagie (who is apparently one who asked "nasty" questions in the session above) and Mark Stephens is also interesting - nothing new, but it shows that they have the same problems that we have: customers with broken PDFs.
https://www.youtube.com/watch?v=g-QcU9B4qMc There are other presentations that I haven't watched yet. Tilman PS: a nice statistics site about PDFBox and other open source software: https://www.ohloh.net/p/pdfbox/
