Halo 3 new system ratings?

[Daniel G]

http://www.bungie.net/News/content.aspx?type=topnews&cid=14994

go to this link scroll down half the page you will see the ratings as follows: BIG TEAM BATTLE, TEAM SLAYER etc...

i dont understand the BIG bar, i do understand the small bars the small bars are colored gold and blue i believe that is your XP but what is the BIG GRAY BAR for?

 

[Dr. Domino]

The gray bars are your current rank in the individual playlist and the colored bars track your progression from one rank to another.