Kanban is a lean approach to agile software development.
Most agile methods such as Scrum and XP are already well aligned with lean principles. Yet in 2001, Brian Boelsterli pioneered an initiative to create a more direct implementation of Lean Thinking and Theory of Constraints to software development. Under the guidance of experts such as David Anderson, Matt Felsing and Geoff Corey a "Kanban system for software development", called "Paceline" was developed and deployed.
So while Kanban as applied to software development is new, Paceline as used in Lean Software Engineering is over a decade old.

Results...

Increase project success rates
Increase productivity and predictability
Increase resource capacity
Leverage current infrastructure investments
Provide transparency of information technology investments to business executives
Mitigate portfolio risk
Instant Agile adoption and improvement
A better technique. Tried and true. Retrospect a platform that is already established