This is a snip from a talk on "Writing Good Dialogue" I delivered at the Write on the Sound Conference, 2009. I know the sound stinks... what the hell am I saying? But at least there's a funny "Gilmore Girls" clip at 3:58.
Here's the point: An easy way to rev up your boring dialogue -- especially between protagonists or in low-tension/expository scenes -- is to make the dialogue "adversarial" or edgy. You don't need actual plot-driven conflict, but if characters don't get along perfectly, it's more intriguing for the reader/viewer.
(Amy Sherman-Palladino is a genius.)
Learn more about writing fiction at http://noveldog.com.