Réf.: Publishing Office Doc's in 10.1 without Adobe Lifecycle
We use PSW from Etrage since 2009. Very flexible (select state that trigger pdf, select object wtdoc type and folder to monitor) and very stable. It also monitors some of our proe drawings to create pdf and finally delete the pdf according to selected state.
It is not opensource but we are very please with the tool and their support even if I rarely need support.