Hey Richard, welcome aboard.
Hope you enjoy the view here.
The effect you're speaking of is a simple one to achieve, although i'm sure that's NOT what you wanted to hear huh? hahaa DOH! [doh]
The specific look of the effect can change drastically in "mood" depending on the context it's used in. I would have to say also though that a lot of those grapgic animations you're seeing on TV are actually done with either a combo of PS and Premiere, or a 3D program.
You CAN "fake" the look easily though, by simply using gradients, and some good ol' gaussian blurring.
Applying the
Clouds filter and colourizing it, then duplicating that layer and blurring the clouds, plus changing that layer's Blend Mode to color dodge/overlay/hardlight can all give decent results.
I wish i knew exaclty which images from FOX TV you were thinking of. I like to be more specific whenever i can. But the exact look of this specific effect, at this moment, eludes me.
Can you think of any better examples than the one from that royalty-free image site?