Just so I have this recorded where I can get to it easy...
ok, to get the Nexus Boot Animation onto a ROM, you need to do the following (this is based on you having ADB running):
1. Have a version of a ROM with the nexus boot animation
2. Open up the ROM zip and look in /system/media and you will see the bootanimation.zip file
3. Extract the bootanimation.zip file from the ROM zip, but DO NOT unpack the bootanimation.zip file itself.
4. Use the following command:
adb push bootanimation.zip /data/local/bootanimation.zip
5. Reboot your phone and Poof, it's there.