Every time I read a post regarding a dragon shout, it seems to imply that it will just "blast back" or "force push" enemies back.
I hope people keep in mind that each one you collect is supposed to be different. Incinerate shout? Hysteria shout? etc...

"players will guide their hero to learn ever more powerful dragon shouts, and then use these arcane powers to supplement other combat and magic skills."
"Over time, players will build a vast arsenal of shouts: over 20 complete shouts in all"
"The amount of time you hold down the shout button is how many words come out"

http://www.gameinformer.com/b/features/archive/2011/01/20/skyrim-s-dragon-shouts.aspx

...that and time are the only ones that have been confirmed and that is easiest to use offensivley.

Other common misconception is that dragons could only be beaten by using shouts.
Why would they? In the trailer you saw the hero shouting "force push" but that didn't even phased the dragon or anything. And I doubt there's going to be an actual attack shout like shouting lighting or something.

There's also the fact that it's overpowered because it doesn't comes from magicka.
It wasn't offically stated but you can be sure there are going to be limitations. Daily shouts, a cooldown timer or even stamina will limit the use of shouts so you won't be able to spam them.

Um, the guy in the trailer didn't yell "force push" lmao. He shouted a 3 syllable dragon shout that we don't know what is. You don't know it was the push.
Also, this isn't Star Wars. Stop calling it Force Push. :facepalm:

Please follow this advice.

I hope its a whole other tier of Combat capability as well as use to affect the gameworld to make things easier for the play (puzzles, circumstances, events) not to supplant my own magic and combat skills, such as I roar, and now I am better at blades. seriously? no I hope its far more distinct and elaborate than that.

Yes he shouted “Fus, Ro, Dah” which means Force, Balance, Push so it would probably push away enemies.

Still I would not call it FusRoDah every time I would use it as "force push" is easier to remember and it's more recognizable.
And I used those quotation marks for a reason.