It's also over 25 years old.Look for a copy of the book "Conservation of Photographs". It is by the people at Kodak and the George Eastman House collection. It covers this topic well.
I personally think that photographs should be attached completely to a backing board, like they are in drymounting. Museum curators can bite their nails all they want; that's their job not mine. However, drymounting becomes difficult for large prints. In particular I will need to mount some 20x24 and larger RC (gasp) silver prints in the near future. It would be nice to know what wet-mounting options there are available in 2011, and how well they work and how they can be expected to last. I know in The Print Ansel goes over wet-mounting FB prints using, if I remember correctly, regular white glue. I doubt that would work for RC prints so I'm looking at either 3M spray or some other sticky product.