Inside the new KitKat dialer APK is some code that suggests that ads are coming to the dialer; there is nothing in the code that tells us if we are talking about huge picture ads, or smaller ads comprised only of text. Luckily, the code also suggests that there will be a way to disable the ads. The dialer in Android 4.4 is getting some love for the first time in, well, ever...
Source: http://www.phonearena.com/news/KitKat-dialer-could-show-ads_id48982
Source: http://www.phonearena.com/news/KitKat-dialer-could-show-ads_id48982