Even though Android L only exists as a developer preview for two devices, and it hasn’t enjoyed a wider public release quite yet, Android M is already being mentioned in the comments of a thread in the Android Open Source Project (AOSP). While the comment was regarding developer stuff that neither you nor I likely understand, this is still a really big deal, and indicates that Google might have already started focusing much of its efforts on to the next version of Android after L.
This doesn’t mean that Android L is ready to be released; to the contrary, there is still a lot that needs to be done. But when technology moves as quickly as it does, it is wise to always have your eyes on what is on the horizon.
What I want to know is this: What will Android M really be called? Milky Way (assuming we stay on the candy bar trajectory that we are on with KitKat)? Moon pie? Marshmallow? Mint? Macaroon? Milkshake? Mousse? Muffin?