I still have about 200 maps for Reach on my 360, and given some time it still boots up. The map copy to the Master Chief Collection is coming soon. What maps do people really want to be able to play in HD and 60 FPS?
Following is a list of all the maps I have on Forge World, excluding a few minor things I made myself, some different versions of the same map, and versions of on-disc maps from matchmaking. I have a few on Tempest and a couple on other maps but Forge World really is where the variety is.

Synapse
"Synergy" v2
2 forts classic v1.1
Alcatraz
Arena X
Awesme
Aerial v2
Affinity
Amphia
Amulet
Ascension Anniversary
Aspirocity
Asylum
Athenaeum
Atom
Atrium
Big Ben
Bird Cage
Bloody Grifball
Blue Depot
Boarding Reach
Boarding Action
Bounce-o-gon
Boxed Cage
Burival v.2
Capacitor
Carnage Palace
Cave-out
Charged
Chimaera
Chiron TL 34
Cliffhanger
Cliffside
Club Crater v3.7
Coagulation
Common Grounds
Construct
Content3
Crash-up Derby
Crossroads 2.0
Crown of Flies
Crypt
Cytocine
Dissension
Death Island
Death Race GT v1.41
Disco
Dogfight v2
Dominion
Dreadnought
Eclipse
Elevation
Embarcadero 7.96
Enclosed
Endzeit
Escher
Evermore
Excalibur
Fat Kid
Flaming Ninja Challenge
Flaming Ninja Challenge 2
Floodgate
Forerunner Grounds
Forge Challenge
Frostbite
Guardian Halo 3 Edition
Get off my lawn
Ghost Town v2
Gibraltar
Grab and Hold
Grifball Coliseum
Guardian
Hascar
HBO Homes
Halo Pinball
Halo Wars
Haloball Court X
Head On
High Noon
Historical Site
Hockey Rink
Homestead
Hushed Apprentice
Hydra XXIII
Imago
Incoming!!
Incoming!! v2
Indomitable Cachinnation
Ionic
Island Retreat 6.5
Javelin
Kingdom
Knockin' Zombs v1
Knockin' Zombs v2
Knockin' Zombs v3
Light Speed Infection
Last Resort v3.5
Lazer Dom
Lookout
Mine Site
Montana Gambit
Musical Chairs
New Venice
Noble Creek
Oblivious
Obsidian
Onslaught
Oracle's Revenge
Orbital
Outskirts
Overgrowth
Predators 2.0
Paramount
Pillar of Autum v.2
Pinwheel
Plateau v5
Popcorn Catchers
Prolonged
Prophet
Pulse
R.A.T. Lab
R3acharound
Rapture
Red Ray Court
Rat Trap
Renegade
Reverence
Ridged
Rift
Riparian v 2.9
Rock-Paper-Scissors
Splender
Sanctum
Sangheili County Jail
Seaside Raceway
Seclusion
Separate Ways
Snipe-a-mole
Snowflake
Soulless Cavern
Speed
Speed!
Station 151
Stealin your flags
Sub-system
Synapse
The Bridge
The Pen
The Pen B
Thrust
Tower Defense
Treasury
Trident
Uplift v2
Urbanization
Utopie
Vanguard
Writer's Mind
Ziggurat
[HD] Jenga v3.0
[S] Ragnarok
Compound
How We Roll!
Project Lyda 2.1
Pulse2
So Bor3d

If you scrolled this far, I have a reminder for you: Customs Night is still every Saturday at 9:00 PM Eastern! Once these maps get into MCC we'll play them, and I expect a lot of other people will too, so I advise everyone to get their DMR and M6G polished up for that.