Personally, I care little for the response time if the issue is taken care of. I have a habit of contacting the host when the issue is completely out of my hands.
The standards for reasonable response time has changed over the years, as more and more hosts have started to advertise 24/7 support. Customers expect ever faster replies. Minutes is the desired turn around time now. Well, the staff can only look into an issue and respond so fast, and some issues are not just a click of a button away. Some can be pretty elusive, require monitoring over a period of time etc.
Thus, for me, it totally depends on the issue. If there's server downtime/slowness involved, I want the host to deal with it as fast as possible. For a small host with 1 tech in the graveyard shift, it would be impossible to reply the 10-20 or more messages from customers and deal with the issue as fast as possible. One must be given secondary importance, and I most certainly hope it's getting back to the customers. Sure, if 1-2 hours pass and the issue is likely to take longer, sending a short synopsis reply to everyone makes sense. But if the issue would take 1/2 hour to solve if given 100% attention, or 1 hour to solve if each ticket would be attended the minute it comes, I opt for the first.