Android L Developers Preview has just got released 2 days ago (26,June) to the LG Nexus 5 and Asus Nexus 7 (2013) Wi-Fi only variant. Today, both already got Rooted, if you own a Nexus 5 or Nexus 7 with L Preview installed you can have Root access.
A New modified version of SuperSU was released to Root Android L. Many users tested the new SuperSU flashable zip and provided a positive feedback that it works fine. Of course, To install SuperSU, you first need to have a custom recovery. Link below has more info.
