Two Asus Transformer TF300s, same JB version, different skin
Asus provides two launchers in their 4.2.1 rom - they differ as you descibed in your question. The one with the notifications in the lower right is the same one as used in their 4.1 rom and the one with the notifications at the top is the vanilla Android 4.2 launcher.

You can switch between them at will by opening settings and then navigating to Device -> Launcher (it requires a reboot to switch).