I purchased the Noble Map Pack, but was disappointed that the game type is selected on the fly by votes. I want to play the new levels but don't want to play capture the flag. Is there a way to filter it so I can play the new maps on Slayer/Team Slayer only?
Not currently no, if you play in the Team Slayer playlist there is a chance that the new maps will appear but only if all players in the game have the DLC installed. At the moment this happens fairly infrequently, the game is still new (and many people will have only just got it for christmas) so people aren't yet bored enough of the standard maps to want to play the new maps.
Until Bungie makes the DLC mandatory (which they tend to do eventually) playing in the Noble Map Pack playlist is the only way to consistently guarantee play on the new maps but still won't let you filter the game types.
The only other way to just play Slayer/Team Slayer is to set up a custom game with a bunch of friends.