Personally, i hated the game. i think there was a lot of reasons for this tho, one being Halo 3 was the first xbox game i had ever played, and i enjoyed it enough to make my own live account and start playing for myself. it was so fun, i loved the multiplayer, and the custom games were great. i was never really into forge, i made a few maps, but it didn't matter cuz my friends made tons and we would custom games on they're maps. i had tried other games like modern warfare 2 when it came out a few months later, but halo was always my favorite. then about a year or two later when i heard that halo reach would be coming out, you could imagine my excitement..... until i got the game and found out what it was all about.
when getting halo reach i assumed it would be a great improvement from halo 3, but instead it was just a huge letdown. it wasnt anything like the game i loved before, it just felt very repeatative. now keep in mind i never played the campaign in either of the games (i prefer the social aspects of games like these) so i really cant judge on that. but what i really didnt like about reach, was mainly the maps. i thought most of the maps were just awful, and alot of them like some of the ones on living dead were the same maps just designed differently in different places on the map. also, i really hated the abilities. the reason i loved halo 3 so much is because it was simple. everyone started with the same armor, and same weapon, therefore no one had an advantage. on some maps it would be a race to the rocket launcher, or the energy sword but that was what i liked about it. if you wanted that special weapon everyone else wanted, you had to battle for it. it was simple, the maps were all very different, and everyone started out equal. also i thought the custom games were far better in halo 3 then reach. the maps were tinier and the games were more enjoyable, rather then on reach where apparently the forge was easier.i never played any fun custom games on reach, whereas in halo 3 everyone had fun doing the custom games.
so really, i hated reach becuase halo 3 was far better, and there were alot more games out there that were just more fun then reach was.