WebDAV is what we ended up using for two different applications. The learning curve is horrible and it doesn't seem to get any better. The inconsistent namespaces are what drove...
We've spent years trying to get SQL and Exchange to work together. One of our big issues which you probably won't have to face is user-defined fields in Exchange...
Excellent points to chew on. What we are putting together is a hybrid of a content management system, a document management system and a photo gallery. There are small files...