WWDC 2013, iOS7: Safari’s redesigned and Siri accommodates better sounds.

 Henceforth, with the Safari’s redesigned, user interface aims to let you see more of your content; the new smart search field helps
simplify searching.  iCloud Keychain aims to secure your passwords and credit card information stored and available on all your devices. Enhanced Parental Controls allow you to automatically block access to adult websites or only allow access to a specific set of permitted websites.
Regarding Siri with new male and female voices and includes Twitter search integration. It also includes: Wikipedia integration, offers Bing web search within the app and the ability to change device settings and play back voicemail.