Automatic PDF renaming based on title
Solution 1:
There is Mendeley, an online research tool that allows you to manage scientific publications.
It has a Mendeley Desktop tool where you can drag and drop PDFs. Mendeley will automatically parse the authors and titles from the PDFs.
Then, you can rename the file by right clicking and "Rename Document Files ...". You can also rename multiple files at once.
It's available for Windows and OS X.