Now that I've had a chance to run the game and (finally) play (thanks to Galen at Origins for the great session), I'm starting to make the setting adjustments to fit the world as it is.
The first question is a bit of a hot topic on ENWorld and other forums. What to do with Dragonborn and Tieflings. The change to Dragonborn is really just a backstory one - the Dragonborn are the result of a magical experiment, the mortals emulating the Gods (in that the aberrations were designed to be weapons); the dragonborn were created and bred to be weapons, turned into slaves, and eventually freed by their own power in a revolt that toppled an empire. They never rose to power, splitting up into various tribes and factions.
The Tieflings, on the other hand, actual have some minor mechanical changes to go along with their massive story changes. The infernal thing is something I generally reserve for bad guys or a major storyline, not your run of the mill warlord. Instead, the Tiefling are out and "Cealdara" (Key-al-dara) are in. Cealdara are elves with abilities relating to cold. The Cealdara will be cousins to the Eladrin and Elves. Outsiders won't know the difference.