When I see these "your favorite {X} from {YEAR}" threads, I immediately wonder if the people involved actually know/remember all the games/whatever that were released in that year, just one specific game/whatever, or if they were thinking about their fav game/whatever & decided to look up it's release date, then post the thread?
Personally, I don't even know what year I bought a given game/video/whatever, let alone what year it was officially released, let alone what other games were released that year.
Bearing that in mind, I'm using a wikipedia list as a reference;
super mario RPG
Dungeons & Dragons: Shadow over Mystara (arcade game)
Bahamut Lagoon
vectorman
sonic 3d blast
pokemon red/blue
x-men vs street fighter (arcade game)
gargoyles
vkimo
They were still making SNES games when the N64 was out? Wow.
That's normal. Companies continue making games for established systems well after a new system is introduced. Sometimes it's because they started a game before the new system's release, sometimes it's because they don't want to risk making games for what may turn out to be an upopular system, sometimes it might be cheaper to make it for the existing system, sometimes they want the large established customer base that the existing system has, and there are probably hundreds of other reasons.
They still made GBC games after GBA was out, they kept making GBA games after the DS was released.