Random semi-organized thought:
I remember when the first map pack was announced, I had this sinking feeling that we'd only see maps as Reach's DLC, rather than new game types. But we did get those, for free, as part of the playlist updates.
With the Flagstravaganza and Action Sack playlists, we got Neutral Flag, Three Flag, CTF Slayer, Speedflag, Speedpile, Power Slayer, Hockey and Hog Potato. (Also, Chess, but not in Matchmaking.)
It's quite the pack of new game types Jeremiah has rolled out; it didn't occur to me just how many there were until I looked back and added them all up. On balance, I'd rather have seen these in the shipping game rather than Headhunter or Stockpile (Speedpile plays just like Speedflag, but with more flags.) I like some more than others, but on the whole it's a hefty chunk of new stuff in the mix.
Thing is, most of them could be built off the base CTF game type if the right settings are included. I hope 343 goes that route to consolodate the core game types for Halo 4, by adding in more flexibility in how the objectives are set up rather than building out fixed new game types. All the flag games could be built from custom game settings if they are expanded with new options: How many flags spawn, if they belong to a team or not, how many points they are worth, how they are carried and scored, etc.
I also hope 343 builds a way in-game to communicate the rules for a game type in the matchmaking and custom game UI. A lot of players clearly don't understand how to play the new game types, especially right after they are rolled out. It's one of the biggest oversights in Reach's matchmaking system, and it's especially odd since there's plenty of space in the UI for it.