I've definitely had a far easier time bringing people with no tabletop-RPG experience into Dresden Files than D&D. Here are some factors that I think contribute:
* 90% of actions boil down to one skill roll against a DC or opposing roll, and there's one unified system for handling them. This is very different from D&D where skill rolls are a separate system from attack rolls which are separate from saving throws.
* You can do almost anything you want with a high enough roll or enough fate points. Maneuvers give a great way to represent all kinds of unconventional combat tactics without worry about whether you have the right feat or enough bonuses to, say, bull rush attempts, to pull it off.
* Fate Points, Stress, and Consequences generally seem to be a much easier system of resources for players to grasp and manage than things like spells-per-day.
* Fate uses small, consistent numbers, which makes math easier. Having to add above 10 is rare, and most bonuses/penalties come as + or -2.
* Aspects and skills allow a new player to make any kind of complex character archetype they want without worrying about difficult or complex mechanics (like multiclassing) needed to make hybrid characters in games like D&D.
* Balance is somewhat less of a concern due to the emphasis on plot and the back-and-forth of the fate point economy. It's much harder to make a character who is weak and will never get the spotlight in Fate-based games than D&D.
