What i think would be a great tool for you guys to have in place is on documentation pages have a Vote for update button somewhere on the pages so you can see where ppl are needing the most up to date info. *because in the real world not everything can be kept up to date 
this would allow more used/ hi priority pages to be kept up to date more efficiently.
also it seams a lot of ppl are using older versions of the software so solid updating of a page might not be in there best interest so a page history would be nice as well so if thee were updates to a page for version 4.1 and it was updated again around 4.7 they can go to a version at or before there own and see what may be more pertinent to them