Tonight I did a test run with my new-found confidence in flash photography. The first picture was taken with an external flash the way it should be: the flash was bounced and directed away from the subject, flash in TTL mode, and camera in manual settings. I got a pleasing exposure rightaway. The second picture was taken with the built-in flash, camera in Auto mode. Notice how poorly exposed the background was. I then used Photoshop to improve the exposure - 3rd image. Even then the image is still poor compared with the first one.
Can't wait to do more road tests with my flash!