Apple updated their OS X 10.8 Mountain Lion developer preview 8 distribution yesterday and with it came a new feature for Notification center -- do not disturb. It looks like a great feature and something that would be very much welcome not only in OS X, but in iOS 6 as well. 9to5Mac's Mark Gurman describes it thusly:
The feature is a toggle accessible at the top of Notification Center that allows users to block incoming alerts and banners. The feature is very important for those who look to focus entirely on the content they are currently working on and do not want to be bothered by new emails, iMessages, calendar alerts, or other types of alerts.
I'd love this for shooting app and accessory videos alone, as nothing ruins a good shot like a spam email or silly tweet showing up right in the middle of a hero shot. For general use, the ability to kill notifications when going into important meetings, when you really need a good night's sleep, or even if you just want to game or watch video without interuption would be fantastic.
Of course, the real solution would be to have location and time based profiles, where "home" could be set up differently from "work", for example, or "day" could have different settings than "night". Third party apps like Tweetbot have allowed time-based notification suppression on their own for a while, but globally that's something only the platform owner, Apple, can address.