Google Latitude and multiple devices - How to prevent location jumping?
There's an app called ALTitude that does allow you to configure those settings per installation (= per device in your case).

EDIT: Purpose of the app - updating your Latitude status/location base on more fine grained settings (update interval, location source).

ALTitude on Android Market

XDA Thread

I'd recommend to configure Latitude to "manual location" and ALTitude to automatic update, but first read through the thread to check if this tool does the trick for you.