A couple weeks ago I got WFRP 3rd as a present. It has happily sucked up most of my free time of late. I've done a lot of reading and analysis, and my wife and I have run several test battles (and a test chase scene and a test social encounter), so I'm feeling I've got a pretty good notion of how the game works.
At this point, I'm in love with the way the game plays. Combat is fluid, the mechanics are easy to grok, and everything at the table just flows smoothly. The GM's job during the game is super easy. Prepping for adventures is surprisingly easy, as well, as the Game Master has a lot of tools, tricks, and shortcuts provided for them that allows you to prep with a minimum of fuss. All the fiddly bits that kept me from ever running WFRP 1st or 2nd Ed are gone, and have been replaced with a system that's just a dream to run and play.
The one area where I'm not pleased, however, is character creation and advancement. While they did a great job of fixing all the during-play fiddliness and book-keeping of the old edition, in the process they seriously watered down one of the things that made the old editions so cool. I never ran it, because it was too complicated, but I always admired the integrated tiers of character classes (there's about 100 of them in the main book for 2nd Ed) and the way they resulted in characters who were realistic and packed with history. But like I said, 3rd Ed sort of watered that down.
Watered down, both in that it has less flavor, but also watered down in that it's all so soggy now you're trapped in a marsh of possibilities. Once I really turned a sharp eye on the 40 existing character careers in 3rd ed, I realized they weren't very coherent. There's a lot of orphaned careers, with no obvious decisions when you level up to a new class. On the plus side, there's not much restricting you, which is nice. But on the negative side, there's no guidance, and it's a point weasel's paradise full of hidden options.
If your group is mostly casual gamers, but with one or two kinda munchkiny min-maxers, I think it'll be problematic. The casual gamers will get mired or lost, and the munchkins will figure out how to break something (starting with Rapid Strike). Even if you're blessed with only good players (as I usually am), the lack of organizational charts will make the advancement process take far longer than it rightly should. I'm thankful that the ugly complicated bits are all shoved off for end-of-the-night advancement, and never rear their heads during a tense in-character scene. But at the same time, I'm scratching my head and wondering why these problems exist at all, when the previous edition was so good at providing the players with a workable balance of guidance and options.
One of my earlier paragraphs mentioned in passing that the flavor had been drained out of the advancement system, but I never really presented evidence to support it. I'll take a stab at it now. In 1st & 2nd Ed, your character leveled up from one flavorful career to the next, so you might go from Student to Apothecary to Barber-Surgeon to Physician to Guild Master, with an immediately understandable progression.
In 3rd Ed, the careers are still flavorful, but the progression from one to the next has been rendered free-form. At first I thought that was cool, because you were never pigeon-holed, and a radically different career might just cost 1 or 2 more XP. Then it was pointed out to me that the Keywords that dictate the XP costs leave a lot to be desired. The worst offender is the "Specialist" Keyword, which appears on a completely random assortment of careers, making it such that being a Hunter or a Pit Fighter gives you an XP break on later becoming a Scribe or a Barber-Surgeon. Between those keywords and the way Talent cards are slotted, the most logical or sensible choice for a new Career is are rarely the most mechanically rewarding next career, and vice-versa. This is a big disappointment for me.
Sadly, the solution to these two branches of the same problem are contradictory. That is to say, the most obvious way to fix the flavor problem is to throw out the keywords and implement a career flow-chart much like what the previous edition had. But since the existing careers are so unconnected, to make a sensible flowchart you'd have to add a lot of additional careers. Which seems a little counter-productive if the other biggest problem is that there's too many things for players to sort through and consider when they're leveling up. Throwing another 20 or 30 careers into the mix will compound that issue rather significantly. And yet, I expect that's exactly what I'll do. So sad...