BackTrack users will notice that Kali Linux is built in a much more structured way, which ensures a more PROFESSIONAL and robust user experience.

Here is a list of the new benefits:

• Debian with an FHS-compliant system: Instead of having to navigate through the /pentest tree, you can now call any tool from anywhere in Kali Linux.
• Streaming security and package updates from Debian: Kali repositories synchronize with the Debian repositories 4 times a day, constantly providing you with the latest package updates and security fixes available.
• Debian-compliant packaging of every tool in Kali: This is where the Kali team has been spending most of its time and effort: relentlessly packaging dozens of useful tools, painstakingly making sure all packages are Debian compliant.
• Long-term packaging and maintenance of high-profile tools: Many of the tools in Kali need to be “bleeding edge”. The Kali team has taken on the task of packaging and maintaining upstream versions of many tools, so that users are constantly kept up to date where it matters. For example, Metasploit is a highprofile tool that is updated with new exploits every week; it was repackaged for Kali Linux with Rapid7’s contribution to ensure a robust user experience.
• Streamlined DEVELOPMENT process: As all source packages are now also Debian compliant, you can quickly and easily get the required sources of each tool, then modify and rebuild them with a couple of commands.
• Bootstrap builds and ISO customizations: One of the many benefits of Kali’s move to a Debian-compliant system is the ability to bootstrap a Kali Installation / ISO directly from Kali’s repositories. This means that you can easily build your own customizations of Kali, as well as perform enterprise network installations from a local or remote repository.
• Automating Kali installations: Kali Linux installations can now be automated using pre-seed files. This allows for enterprise-wide customization and deployment on multiple systems.
• Real ARM development: BackTrack 5 introduced support for ARM hardware. The ARM build-bot was a modified Motorola Xoom tablet, which - suffice to say - didn’t last for long. To help remedy this, Offensive Security has donated a Calxeda ARM CLUSTER to the Kali project, allowing reliable and long term development of Kali Linux ARM images. Note: Metasploit Community and Pro are not SUPPORTED on the ARM platform.
• Complete desktop environment flexibility: Kali’s new build and repository environments allow for complete flexibility in generating your own updated Kali ISOs, with any desktop environment you like, no matter whether you prefer KDE, LXDE, XFCE, or a custom desktop environment. 
• Seamless upgrades to future major versions: Another benefit derived from the move to a Debian compliant system is the ability to seamlessly upgrade future major version of Kali. No longer will you have to reinstall your penetration testing machine to upgrade to a new Kali version.

BackTrack users will notice that Kali Linux is built in a much more structured way, which ensures a more professional and robust user experience.

Here is a list of the new benefits: