For me, the benefit is that I need to write commentary about each video clip, and PDFs enable me to write the whole document in Microsoft Word with all its many capabilities (automatically built table of contents, footnotes appropriately located and automatically adjusting to text additions, hotlinks to previous sections of the document and to example utterances cited on previous pages, etc.) and simply press a button to convert it all to a PDF (transferring every one of the just-mentioned convenient features along with it). The downside is that I have lots and lots of video clips, and after-the-fact editing of a PDF is highly limited (no re-flow the the next page, for example). So if I make a change of any magnitude I have to re-link all the videos again, a time-consuming and tedious task since I want many different viewing parameters from their defaults, and there's no place to specify my own defaults (despite repeated requests to their wish list). The best solution I've found, which is not too bad, is keyboard macros provided by AutoHotKey. Oh, and of course, having to tell my users that they need to have Apple Quicktime, a recent version of Acrobat Reader (not Preview), and use native browsers (IE for windows, Safari for Mac - although Firefox does work for my site in Windows 7 and Vista). But I will have a rather restricted user base - mostly linguists interested in sign language grammar!