Gnomes, Deep Gnomes, Duergar, and Half Orcs are both at the top of my list and seem almost certain to make the cut. I think that would be a good place to leave it, honestly, since I'd like to see each of the races get as fleshed-out RP opportunities as possible, but if we are talking about even more race....after that, maybe Aasimar? -they cold be interesting with all the Infernal focus we are seeing in the game so far. The Genasi never held the same appeal to me so I wouldn't be too disappointed if they didn't make it in. Orcs and Hobgoblins similarly I wouldn't mind having in, but all of those are pretty much in the 'it would be cool to have them, but I wouldn't particularly miss them if they weren't in' category.
A lot of the other stuff, Tortles, Goliaths, Kenku etc, I don't really think would be a good fit for player races. NPCs? Sure. Party members? I can see it. It would take a lot of work to flesh out these exotic races to be fully playable for us in a way that feels natural. IMO Larian already is going to have their work cut out for them between Drow, Githyanki, and Duergar.
Dragonborn, like a lot of 4e stuff, I don't particularly care for. I don't want to play them, and I'm actually rather selfishly hoping I don't have to see too much of them in game and can avoid interacting with them too much. Warforged... Eberron was designed as a standalone setting, so I wouldn't be particularly enthused to see warforged running around in a Forgotten Realms game.