3E killed my DnD game.
When 3E first came out I was overjoyed and posted happily all over Eric's original board. So many of the things they were doing sounded fantastic. 3E was, quite honestly, an amazing step forward for DnD. I still believe that. It was light years ahead, in terms of design, of 2E (though I loved Player's Options).
The problem was that, in practice, all of those awesome cool pieces, when put together, became more and more cumbersome as the characters increased in level. Also the ENTIRE wealth-by-level thing was a very hated and loathed feature at my table. The game bogged down and became ... tedious. The Full Attack option, once a character got around 3 attacks, was where it began. It then just got worse with Buffs. "Does my Natural Armor stack with my Deflection bonus? Does that change my Flat-Footed AC, or my Touch? Oh, and this round I'm going to get Luck, Divine, and .... let me see .... a Dodge bonus to add to my Inherent and Enhancement bonuses. What's my Flat-Footed AC now?" Add in Summoned monsters and balancing creatures with their own stacking buffs and round to round combat just became boring. So much so that I dreaded making up the next adventure and the co-DM of the group just flat out refused to run the system. People didn't even want to update their character sheets after a game. They wanted to play, not be book keepers.
And so we just left the system behind and played D20 Modern which was a beautiful system to run sometimes, and Rolemaster/MERP where we could get all the "complicated" we wanted but at least be able to sever limbs for our trouble.
3E did a lot, a LOT, of things right. The simplified mechanic of d20 roll + modifiers vs. a DC. Templates. The unification of the Spell Lists. Skills (though I had to give everyone a blanket 4 skill points extra to get into the ball park of where they should have been). Feats. All of those things were amazing. They were the things I read about that got me excited about the game when I had been convinced that 1E and Player's Options would be the only DnD I ever played. They were the reason why I gave 3E a shot.
But in execution they didn't work out as well as they could have. Why? Because as the game progressed it took nearly as long to prepare or manage things OUTSIDE the game as it did IN. When my group and I get together we get together to play. The characters each have their goals, and their plots, and they have the mysteries I give them that they're trying to unravel and they want to get into some rough scrapes and spill a little blood on the ground. They're completely not interested in keeping track of how many bonuses they have and whether they're stacking them correctly, or of calculating all the cascading effects that changing that one magical item at the end of the game had on their character. Sure, it made more sense the way things were set up, but in the process turned our favorite game into a chore. I mean, the players would PAY the rules-lawyer of the group to update their character sheets when needed.
Does 4E sound perfect? Hell no. But it sounds like they're making sure that the game is going to have more "play" and less worrying about the trivial. In creative writing the author is advised to "not write the boring parts" and I hope that 4E follows that advise.
Of course, those boring parts are the reason why some people play. Hell, I met two guys once who wanted to join our group and asked if it was "all right" if they "role played" their characters when they weren't at a game. It took me a few minutes to get that they didn't want bonus experience points but just wanted to role play their characters going about their day and thought they should have the DM's permission or something. I let them know that they should probably find another group. No harm, no foul, tastes just differ.
Hopefully 4E can do what it claims: bring a fun, fast-paced game back to the table that allows us to insert some roleplaying where the book keeping used to be. And hopefully Pathfinder delivers the more involved, nuts and bolts, keep track of everything style that fans of 3E love. I'm just happy that I'll be able to kick in a door again and take someone's stuff without having to look up the synergy bonus that brass fittings give to a wooden door's Hardness rating.