The vulnerability could potentially have a serious impact on a large scale if it were exploited so I would agree that it is a major issue that needs to be addressed ASAP. On the other hand, DNS was never an absolutely secure protocol to begin with so to think that this news means you need to storm into your CEO’s office and tell him everything needs to get shut down mid-day so that you can install the patches would be overkill.

Update your name servers as soon as possible to mitigate the largest risk. For everything else I would treat this vulnerability equal to any other vulnerability that impacts the majority if not all of your systems. Follow your normal procedure for patch management and get these applied in a timely manner. If you don’t have a normal procedure….then now is a good time to put one together. It doesn’t have to be done today, but I wouldn’t put it off too long without a really good reason.