When I save an Illustrator (CS4 and below) file that has a document title and an author in the File Info tabs only the author field is properly transferred to the metadata of a PDF when using Save As PDF. The title field of the PDF gets the file name ("map_data_2006") and not the document title ("Map of Data in 2006"). How do I keep from re-populating the PDFs with metadata (which increases the file size after a resave) which is already stored in the AI files?
Just a guess: the usual problem is XMP not being synced across different apps, so field names and their values do not match. You may even need to define a custom field to get this working properly, so check the respective options in Bridge and Acrobat. if that doesn#t solve anything, then it may be a design limitation in how AI implements PDF metadata.
I have exactly the same problem with Adobe Illustrator CS5. The rest of the Adobe Suite Products do save document title to PDF metadata correctly when exporting to a PDF file.