Now, for the game itself, it is harder to say and I assume this edition will do what all previous editions have done. There will be a period of confusion where people like me wonder if a relatively simple system needed to be streamlined and simplified some more. There will be a six month stretch where people piss and moan about Wizards of the Coast having the sheer fucking GALL to be a business that needs to make a profit and release a new edition. The obvious period of people complaining that they're being forced to buy new books (particularly ironic given how incredibly broad the official expansions have been, never mind third party supplements meaning that almost every concievable setting and rule has been done twice over) The Open Gaming License advocates will whinge for some time too about how this is going to destroy their business (of mainly providing pointless, shit supplements) but overall this is going to be a success one way or the other.
The basic first impression is that the streamlining of the rules and generally bombastic illustratative style means we're supposed to be playing much more epic games. The system feels a little like the new World of Darkness rule set and this is definitely for the positive, particularly for magic users who are now in a position to be chucking out a lot more spells and contributing to every fight, not just the first tough one of the day. Where previously a lot of D&D games felt like a protracted session of Baldur's Gate where premature use of your Mage's sole fireball would mean the party had to head back to town to rest for eight hours and tended to make them a somewhat useless knifethrower at the back, praying that no one flanked the party, now they can keep on trudging until the bitter end.