Damn people! It's only been out for two days (if you count New Zealands[sp?])! How could you possibly be worrying about earning the Meta Game achievements already?!?
Of course, this is x360a...kinda the point.
Oh well, just decided to post this http://www.bungie.net/News/content.a...ink=h3campaign
It gives pretty much any tips and trick that you need to know about the skulls and special kills so that you can earn the highest score possible.
With this link and the previousely posted screenshots of the scores for each enemy, you should be well on your way to earning those achievements.
I on the other hand have to wait until tomorrow before I even get to play the game for the first time...you lucky bastards!