Here's Play Service 4.2. Thanks to +Sam Meng
for the APK.
Not much other than this sweet
new icon and the new Chromecast SDK stuff.
There is this suspicious string: <string name="people_google_voice_phone_label">Google Voice</string>
but I don't think it's used anywhere yet.
There is also (maybe?) some new Play Games screens, but I never touch Play Games so it's hard to tell.https://drive.google.com/file/d/0BxI1YpjkbX0OZzFpeWxWZkw4LUE/edit?usp=sharing