The following comes from a Eurogamer interview with Infinity Ward executive producer Mark Rubin...

"Everyone knows that can happen there, and someone's going to use it intelligently. Some maps have traps you can set, that you can then use as part of your play strategy. So it's not always about destruction. Destruction isn't what everything is, from a dynamic maps sense. It's changing things. It's moving things. In some maps we haven't talked about, it literally is moving objects out of the way, or moving them back into the way. It becomes more of a map strategy rather than just, oh it looks cool to blow up a building."
Rubin says if everything was all about destruction, the maps would become flat and boring. I guess he has a point!