http://www.certainaffinity.com/uncategorized/forging-game-modes-in-halo-2-anniversary/ Looks like Certain Affinity's done a good job at providing documentation for what each game label does.
Found some extremely notable information for Infection. Looks like you can pull off some magic with inf_flight_reveal and inf_flight_remove after all: Like in Territories Incursion, you can label any object so that it is either activated (revealed) or deleted (removed) once a given Flight Zone becomes the next zone. Label an object inf_flight_reveal and give it the Spawn Sequence of a Flight Zone if you want that object to start spawning once that Flight Zone becomes the next zone. Label an object inf_flight_remove and give it the Spawn Sequence of a Flight Zone if you want that object to be deleted and stop spawning once that Flight Zone becomes the next zone. You may wish to reveal an object once a certain Flight Zone is next, and then remove the object once a later Flight Zone is next. To accomplish this, set both inf_flight_reveal and inf_flight_remove labels on the object. Then use the first digit of the number set in the Spawn Sequence to refer to the Zone for which it should be revealed (e.g. 2) and the second digit to refer to the Zone from which it should be removed. For instance, if you wanted a Rocket Launcher to start spawning after Zone 1 is complete, and stop spawning once Zone 4 is complete, you would give it the label inf_flight_reveal, and the label inf_flight_remove, and set the Spawn Sequence number 25, because once Zone 1 is captured, 2 will be under attack, and once Zone 4 is captured, 5 will be under attack.