Picked up my copies of HEROES OF THE FALLEN LANDS and the RULES COMPENDIUM today! I have to admit, I'm pretty excited about the Essentials line. It makes me want to start a fresh, new campaign based more on the traditional dungeon crawling aspects of the game.
Just flipping through the books, I can tell these will be great references to new players or older players who have yet to play 4e. The books feel more "classic" than the actual PHB and DMG for 4e, and I think that will be a big selling point for the line. I also like the format of the books. When I first heard of the change from hardback to a smaller, digest sized paperback, I was a little dismayed. The end result, however, is quite nice and will be of more use to players and DMs at the table.
Oh, well, I better stop. I'm starting to sound like a WOTC spokesman.