Google recently posted Android L preview images for the Nexus 7 and Nexus 5. This is the first time Google has decided to offer a developer preview of an upcoming Android version and no one knows how the operating system would work. Would there be any updates? Would the OS evolve over time?
The new Android L versions have the build number LPV81C and they are two-days newer than the previous release; they include support for Google Fit, among other things. No new and huge changes observed otherwise.
You can find the preview by clicking HERE. The preview is found on Android Developers from where you can download it and flash it on your device. You will most likely need a full wipe of your OS though.