How to add a background color to a text layer?

I've seen in several typography videos where text areas appear to have a background. Is there a way to add a background color to a text layer?

I've achieved a similar result by scaling a solid color layer, and parenting it to the text.

An example would be @0:35 in this video: http://vimeo.com/10271606

Not sure if that was After Effects or Motion.

I've also seen this affect with typography work where text swings down like a sign, and it has a colored background.

I'm wanting to change the background of the text layer, not the text color itself. I'm on CS5 btw.

Parent a colored rectangle to text layer, put that under the layer with the word that needs it as background and select track matte inverted- you will get the effect from the example you posted. Of course if you need to put background to one word in a line, you will need to have that word on a separate text layer and if you need to make the background appear and disappear living the word behind, you need to duplicate the text layer with that word and place one under the background layer + change opacity.
Hope this is clear...

Tudor "Ted" Jelescu
Senior Compositor/VFX Artist
Bucharest, Romania