In a webconference today, Jeff Taylor, founder of Monster.com, had a bullet point that said, "Customer is silent - please fix what hurts." Taking that completely out of context [grin!], this is how most customers interact with digital libraries. Customers (patrons) generally don't contact a digital library when things are going great. They contact the DL when something is wrong. We can't predict when something is going to go wrong, so we need to be available -- in some form or another (like IM) -- all the time.
When a patron is using your digital library and she needs a hurt fixed, can someone at the DL be contacted? Can the hurt get fixed in the now (in the moment)? If your answers aren't "yes", what do you need to do to change so that when the customer is not silent, someone is there to listen?