Yes iOS 7 has started updating all over the world every supported iPhone, iPad or iPod Touch but really I am not that happy with some of the features. It is impossible to change the 3G network to 2G network; this is one of those things that dissatisfy me. Instead today I am going to change your mind not to upgrade but stay with your jailbroken iOS 6 and bring the feature that you want from iOS 7 through tweaks.
You will be pleased to hear that some of the known tweaks from cydia have the same functionality. Let us take for example Zephyr or Auxo. But there are also tweaks that copy the design of this new iOS like the famous iOS 7 theme. But this will not change the Dock to that of the new iOS. Instead you will need to use CopyDock which is the closest you can get in terms of looks of a dock from iOS 7. It has the same graphical design of a flat surface but it is not the same. Because of its simplicity it is free from BigBoss repo via Cydia.
There a lot tweaks that offer not the looks of iOS 7 but also new graphical designs.