jezzzy:

i think it was COD who when they put out new maps they made a new map playlist so the people with the new maps could play together when they like. then a few months down the line they made the maps free (i think) and merged the playlist so because everyone then had the maps the play chance was even.

i dont know why glacial revine has no stats on the site, maybe its just a stat bug? but the other new maps have barely any games on them too. maybe hardily anyone has bought this DLC and matchmaking simply cant find 6 players to playlist GR? 

Dunno about CoD but Halo 2 did this (seems a more suitable game to mention). Robot should've waited on the first DLC and released them both for 800 then we might not be having this issue. 40% is a huge ammount but people just don't buy the maps because they don't think they'll get to play on them so no-one gets to play on them so no-one buys the maps.