And it's aparently not.
I've just compiled an APP with the latest google play services, which I've set on gradle as:
compile 'com.google.android.gms:play-services:+'
But when I open my APP, there's a huge warning.

And in LogCat:
W/GooglePlayServicesUtil﹕ Google Play services out of date. Requires 5208000 but found 5089070
If I open google play (pressing Actualizar button), I can see my Google Play services are totally updated.
This is happening on a genymotion emulator aswell as on a nexus 5 device.
I've tried things like:
compile 'com.google.android.gms:play-services:5.2.8'
However it complains:
Error:Could not find com.google.android.gms:play-services:5.2.8. Required by: :mobile:unspecified > :BaseGameUtils:unspecified
Any tips?