I haven't had a chance to play it yet, but I have read through the main bits and my general impression is quite good. They've flattened out the power curve quite a bit and fixed a bunch of things that were clunky in previous editions, and all the fixes are things that make you say "well OF COURSE that's the right way to handle that." There are at least two significantly different ways to go with every character class, and they include a number of character types that were always popular but hard to build.
I'm particularly impressed with Backgrounds. Backgrounds are a standard part of character creation; they give your character a couple skills, some gear, and a benefit. You also pick a couple personality traits, a weakness, a thing you care about, and a goal or ideal, all related to the background, and here's where it gets clever: if you roleplay those characteristics, you are rewarded with inspiration, which you can use to get a mechanical advantage. (And while you can make up your own, all of the suggested characteristics are definite and concrete things that are easy to latch onto.) And they did a good job picking the nature of the characteristics; I sketched out four different character ideas, and with each of them, after I figured out the background and thought about what kind of person would have those characteristics, I felt like I had a really clear picture of the character's psychology and how they would behave. So it's a very well-designed mini-system for encouraging roleplaying.
I'm looking forward to playing at some point!
(I was working on a longer post, but then my browser ate it. Grumble! But this was part of it, and hey, for once I'm sharing an opinion about things instead of just recounting What I Did Last Week...)