Myself I much prefered the 3rd edition, the first 2 still used an obsolete % system that I never really liked, it was too hit or miss and with percentages your starting character had a much too important chance to fail even simple tasks unless you munchinked combos.
3rd edition use a pool dice system that is much easier to use once you are familiar with it.
True, the initial release came with a lot of stuff with it (card and token mainly), and this made many players angry.
Myself I rather liked it, FFG has always been very good with material components, and having cards with the special rules instead of having to reference a book or printing shits with the exact same information was in fact time saving, but I can understand people prefering more control.
FFG did listen to feeback about it, and later released a resion of the rule without the components but with more text (no card, but pages and pages with the corresponding powers), if they had released like that maybe some players would have liked it better (but then, by printing the information in both the book and the cards, probably some people would have complained that they had to pay for more if they wanted both)
Well, to be fair, after a certain level, the dice pool became unbalanced, a character with a lots of skill levels and a maxed attribut becoming overpowered, but this is not really different than the old system with a character with 95%+ in combat skills, but it can take years of playing to reach this point for most groups, and before that the game is much more fun for the players from my point of view.
Also for information FFG didn't stop there, they used the good ideas from WHFRP 3rd edition and improved even more with the Star Wars RPG.
One big difference is that in Star Wars the dice pools grox smaller : when in Warhammer you add the dice from your ability (Strength for exemple) with the dice from your skill (like Close Combat), in Star Wars the higher of the two value is the number of dice that you roll, and the lower value is the number of dice that you replace with a better die.
So someone with Dex 3 and melee 1 would roll a total of 3 dice, 2 default 8 sided die, and one 12 sided upgraded die
This make player progression smoother, and reduced the delta between a vertan and a beginner or average guy while still letting the veteran feel that he is much better.
Also it prevent dice pools from growing too large.
I would have liked to see FFG do a 4th edition of WHFRP using this accumulated experience, too bad that now we will never get it.
As for the news of a "new" edition still using the old % system, for me it's meh, it's the sign that they are not even trying to improve and just printing money by going after nostalgia.
Well, it's still better than to see them an AoS rpg and completly forgot the Old World I suppose ...