My own thoughts about the matter that may tie or now with what's been said.
I started seriously not liking 4e. But over time I realized that while some flavor of past editions have been lost it solves many other things.
One perfect example is high level play. I'm a Story Hour reader, and remember fondly Piratecat's, Sagiro's, Sepulchrave's and Wulf Ratbane's story hours. I've noticed how starting at medium level almost all gameplay bogs down on divining what the bad guys are doing and where they are, foil the mind blanks and counter divinations with some clever rules lawyering and protect themselves with their own counter-divination measures. In between combats, it quickly becomes a sucession of legend lore, vision, scry, find the path, teleports, prying eyes, magnificient mansions, mind blanks, and wind walks. Then combat happens and it's usually a 30 minute buff routine, then a teleport, followed by 2-3 round brutal affair with multiple save or die spells and people rollercoasting from full health to death and full health again in a matter of seconds. While I don't believe it can't be funny I think there are alternatives to that and 4e offers a valid one.
Second, I remember having a serious lot of trouble designing adventures past 11th level. Thankfully tools for applying templates and designing NPCs became common, because statting anything was a complete nightmare, and caculating the starts on anything like a half dragon ogre barbarian was Hell.
Third, I remember being so used to 3e's simulationist philosophy that I couldn't conceive anyting else. It was actually my fault, not the game system's – though it has its part in it. I'll clarify with an example. I once tried to create the typical BBEG necromancer, a otherwise normal guy who had an undead army. 3E being 3e, he had to follow the same rules as PCs, so there had to be an explanation about how to he was able to do that. A custom prestige class? A special magic item (and what if the Pcs got it?), a gift from a god (wouldn't make this the god the ultimate BBEG?). In 4e, NPCs don't follow the same rules as players; combat stats are an arbitrary mechanic, not an attempt at simulation. So if you create a human solo with 5 times the amount of hit points a player of that level would have you dont feel, uh, guilty? Yes, that may be the word.