Android 2.1, Eclair, Push
Looks like Google is starting to push Android 2.1 source code to the Android Open Source Project. The files are marked Android 2.1_R1 Snapshot. This is great news for custom ROM developers as they can now really start enhancing the Nexus One’s Android build and adding in some new features. Also, this will make porting of Android 2.1 to other devices a little easier for ROM developers, such as those found at XDA.
UPDATE: A little more information from one of the developers themself: Google Group
