One of the reasons I work on a Mac rather than a PC is to avoid the constant interruptions from Windows alerting me to crucial software updates, not to mention its nasty habit of insisting on installing 48 updates before letting me shut down my PC at the end of the day. Mac OS X isn't completely innocent in this regard, but Mac OS X 10.9 Mavericks gives you more options than previous versions of OS X did in scheduling updates. You can set up Mavericks to install updates automatically, and if you want to go the manual route, you have more options now for delaying an update when you receive an alert.
First up: the "set it and forget it" option. You can set up automatic updates by going to System Preferences > App Store and checking all the boxes so Mavericks will check, download, and install app and system updates as they become available. And if you are signed into your account in the App Store, you can also set up automatic downloads of apps you purchased on another Mac.
If you don't trust Mavericks to avoid updating itself when you have 14 windows and 27 browser tabs open in the middle of the afternoon, you can opt to install updates yourself. And now, you are given greater control about when to install updates after you get an alert.
When you open the App Store to see which updates are available in Mavericks, you'll notice there is a new down-arrow button next to the Update All button. Click on it and you'll get four options for scheduling the updates: Install Now, Try in an Hour, Try Tonight, and Remind Me Tomorrow.