It is a very interesting one because even though a lot of us know that the real (or should I say the most accepted) pronounciation for Hermes would be air-mes (or something similar to that), I always want to confirm with some French-literate members here. We all know that H in French is silent, however, S is also silent at the end of a word (eg Troi"s", Avenue De"s" Champs Elysee"s") , so wouldn't that makes Hermes "air-may" instead? Compare the end of Des with Hermes, and Des is pronounced as "day"... anyone?
I know discussions like this might never end, and we probably wouldn't come up with a definitive pronounciation unless the Hermes family member comes out and clarify.. :shame: