A little more background that may be helpful, this is more or less what's happening:
White balance is applied when the raw sensor data is turned into an image (jpg). If you shoot JPG's, this happens in your camera and it is more or less "hard coded" into the JPG image data. Therefore, when shooting JPG's it's best to be mindful of your white balance setting on the camera.
If you shoot raw, the camera simply stores the white balance setting as data along with the raw sensor data. When you import the raw photo into Lightroom or whatever raw capable software you might be using, it will display the raw photo with the white balance that was stored in the camera, however since you are working with the raw sensor data and haven't yet processed it into a final image / JPG you have the opportunity to select a different white balance (as well as numerous other settings that your camera would be doing automatically if you shot JPG's).
This is generally how I work and it's nice because it's one less thing you have to remember to set on the camera before taking a photo since you can tweak it after the fact. It's also nice because sometimes none of the camera's preset white balances are quite right, and it gives you an opportunity to fine tune on your nice big monitor when you have all the time in the world versus when you're trying to get a shot off.
I have found that on the Panasonics at least, the "Auto" white balance only works decent on straight sunlight. If it's cloudy, shady, or artificially lit, it's pretty much always off. The vast majority of point and shoot users never mess with their white balance and that's why you see all different shades of strange colored images that most people have just come to accept as normal. However, once you start tinkering with the white balance, you realize how far off the cameras usually are, and how much more natural your photos can look if you just take a few sec to set it before or after shooting.
Many thanks!
