I'll preface this by saying that I've been a fan of 4e practically since it was announced.
I really like the layout of the new books. To me, the books, the PHB especially, should essentially be the quickest way to say "Here, have fun." You should be able to quickly thumb through the PHB, find a few things that look fun and interesting, throw together a character in like 2 hours tops (going from when you first crack open the PHB to when you walk through the tavern door) and then just start having fun.
Now, don't get me wrong, I really like 3.5, but you simply could no do that. Learning the system took a considerable investment of time, especially if you were a spell caster. In 4e you can transcribe an entire power verbatim from the PHB and take up only 1 side of an index card, there is a very short list of spells you can do that with in 3.5 AND every single power in the game follows the same straight forward design.
The mechanics should be delivered in the quickest and cleanest way possible. Both mechanics and fluff need to be streamlined IMO. The quick 1 or 2 line phrase at the heading of a power is just right; it gives a soul to the numbers below without drawing your attention away from them. You don't need a page long description to say what a fighter is at this point, a single paragraph would do just nicely. Don't like what you've read? Then go to the next class my friend, it will have it's name and most the vital information displayed prominently next to a full color illustration of that archetype on a page all to itself.
Because everything advances at the static 1/2 level, most of the tables from the 3.5 PHB just go poof, and you can convey the classes' progression in a few simple bullet points. The whole point of having mechanics in a game like D&D is to ensure that everything runs smoothly, and everyone can have fun. I think that 4e has done this better than any edition so far, and because I have always liked D&D, I will like 4e even more.
That's just my opinion.