well Dragonborn don't fit in my currernt world. Tieflings and Assimars fit on one contient but not the other. Half-orcs and gnomes were never part of the world.
Im still undecided on the possibiltiy of doing a new world from scratch. If I do, dragonborn will get a place at the table, presuming they work as a race.
My players are bigger on new classes -warlock, beguiler, cloistered cleric, duskblade, spirit shaman, and scout. As well as every core class - except ranger, oddly. I have no doubt that everything will be tried.
As for races, only tiefling x2, half-demon, celestial (templated) elf, and core have been used, except by one ex-player who played in rapid sucession: goblin, dragonborn, elf. 1/2 fey, human, and exotic human.