Oh goodness yes.
If you're in an area with white ceilings or white walls, the tile/swivel will allow you to bounce your flash, effectively making it a flash modifier. On-camera flash is harsh and flat, respectively because your apparent light source is small and on-axis light flattens the shadow detail of your subject. Ultimately it looks unflattering on your subject. Bouncing the flash on a wall or ceiling will both increase your apparent light source making it softer (like an umbrella or softbox would), and alter the direction to give a more natural shaded look.
Not only that, but like the T3i, the T4i has a master controller in the pop up flash. So you can use the 430EX as an off-camera slave. Meaning you can use shoot-thru umbrellas, you can use softboxes, you have a lot of creative choices, and thanks to the built-in Canon wireless control you only need one slave-capable flash to get started.