You can use a plugin for locale located here
Locale GPS Plug-in v1.1 Application for Android | Tools to have locale also turn your gps on or off for certain situations. I have locale turn gps off once I arrive at home or work because it's not doing any good there as I'm stationary. It turns back on for my default situation so it can be of use for other location aware apps. I also have wifi turn off when I'm at work and on when I'm home. Turning gps off at work and home probably saves a good portion of battery usage but I've never really compared.
Also, my battery life seems to be about the same after the update as it was before. Nothing scientific though, just a guesstimate.