When you love a game and put hundreds of hours into it, it's easy to get attached to its many subtleties. In Halo 3 I played so many custom games with my friends with specific maps and settings, that I feel a little empty not being able to accurately recreate that experience. I don't think the initial maps we're given are as good as Halo 2 and 3 for the types of games I prefer, but I'm loving everything else (campaign, character customization, and of course the amazing Forge World).