So apparently there's a supposed leak of an early version of 5e on the SomethingAwful forums.
Pasted here if you want to look at the discussion. (This is obviously thirdhand and not official, but we can talk about it anyway.)
The system for ability checks/skills/what have you is pretty fucked if it's anything close to what I think it is. I'm still not sure if your modifier is the whole stat, the stat minus ten, the stat minus ten modulo 2, or some other piece of mathematical witchery, but it doesn't actually matter because it will break no matter what. You'll have weird things like someone with a 16 Strength being able to leap a pit without fail every single time, forever, while his 15 Strength buddy enjoys a 50% chance of failure on the same task (and that's if we're being generous and assuming your modifier is your score minus ten to make full use of the +1/-1 racial modifiers). So we still have some ability score numbers being much more important than others, except now you can never know which ones they are, and instead of being a 5% improved chance of success important, they are a 50% (or more) improved chance of success important. Alternatively, if they decide that your stat is the modifier, you'll have the RNG breaking from level 1.
This is admittedly largely math based on bullshit because I have no clue what the actual rules are here, but it's based on bullshit that Monte Cook has given us and these alleged playtester reports, so it counts for something.
Oh, and apparently there are six defenses, one for each ability score. But that's honestly par for the course by now.
(Also, I have no idea why they all seem convinced that it would be better to base 5th edition on 4e than 3.5.)