They are startlingly unashamed in the changes they made. This is where the books, at first glance, will bother people who are predisposed to not liking 4E. The books dont at first glance seem "comfortable and similar and familiar." They used a new layout and new organization. Looking back on all the PHBs since the first AD&D PHB the format has been about the same. This one changes it all up. And that first impression is a bit startling. Plus, some of the new stuff is front and center. Heck, dragonborn are the first player race. The first bit of art in the book, starting from teh first page, is a dragonborn. That is new content. They dont try to ease you into it. I have said in the past, they didnt just kill sacred cows, they hung their carcass in the store windo--but I think this is a good thing. If you are going to make changes, dont %+%+* foot around the issue, jump in and do it. And that is what they did. I firmly believe that if people want to not like 4E, there is enough there on first glance to support their fears, BUT once you look past that first layer, you will see this is not only D&D, its is better and better organized and all the changes are improvements.
I probably won't be reviewing them 4e since I don't plan to play it anytime soon. By the time I might get around to writing such a review, the conventional wisdom will have already spoken definitively on the subject.