A new dinosaur named Tatankacephalus cooneyorum, was recently unearthed in Montana.  For me it's not a particularly exciting find.  It's a rather standard addition to the anklosaur family, a group of armored dinoraurs with club like tails.  It is surmised that because of their thick shells and club like tails they would be able to bat around smaller dinosaurs and larger carnosaurs such a Tyranosaurus Rex would be hesitant to attack because a broken leg would almost certainly mean death to one of the creatures.  (though there is mounting evidence that Tyranosaurs may have cared for their own because creatures have been found with signs of broken bones that had healed.)

 

It's text book evolution, a transitional fossil between early small creatures whom hadn't fully developed the Viking Helmut like skulls of their decendents but were clearly farther along than there ancestors however.  Which makes it important for making the case for evolution but other than that standard dino find.  Walking twenty foot tanks are kinda neat though.