I don't think we'll see a Large player race in 4E, ever. We already got the goliath to cover that niche.
I'm not sure any of the other races introduced in the 3E 'Races of ...' series had enough traction to put them into a 4E PHB. Illumian, maybe - have they been a popular choice in 3E?
Kalashtar strike me as being too strongly tied to the Eberron setting.
Of course I'm hoping for Darksun to be the setting after Eberron, so the Thri-Kreen would make sense. They're not setting-specific, since they existed since 1E, so they're a good choice to include in a PHB.
I'm not sure any of the other races introduced in the 3E 'Races of ...' series had enough traction to put them into a 4E PHB. Illumian, maybe - have they been a popular choice in 3E?
Kalashtar strike me as being too strongly tied to the Eberron setting.
Of course I'm hoping for Darksun to be the setting after Eberron, so the Thri-Kreen would make sense. They're not setting-specific, since they existed since 1E, so they're a good choice to include in a PHB.