But seriously, folks...
I'm very impressed with the book itself as well as the rules. The book has some nice artwork, but it seems to steer clear of the "massive spiky armor and 2' wide swords" aesthetic that plagued previous editions. If I had one stand-out complaint about the art, it would be the depiction of halflings. Not only are they shown with shoes (a pet peeve of mine), but their legs are uniformly spindly, making them look like walnuts propped up on toothpicks. The pages have a faux-parchment look that I suppose is unavoidable these days, but it doesn't interfere with reading the text, as there isn't any actual design that shows through behind the text, which was a problem with certain other books in the past.
The rules expand on the previously-released Basic Rules and the boxed Starter Set. We now have a full line-up of character races and classes, with suitable backgrounds, options for customization for each class (bard colleges, barbarian paths, etc.), and the like. I don't personally understand the need for wizards (get spells by studying), sorcerers (get spells through raw/wild magic), and warlocks (get spells through pacts with powerful beings), but I know I'm in a minority in that and have reconciled myself to the fact that not everyone is a Grognard. I won't probably ever play a sorcerer, but I can see how folks might like it (it's very DCC in feel, with a big random table for "wild magic surges" that happen when you roll a 1 when casting a spell).
I am particularly fond of the sprinkling of references to the various published D&D campaign worlds throughout the text. Greyhawk, Forgotten Realms, and Eberron even have deity lists in an appendix, but there are references to Dark Sun, Blackmoor, Planescape, Mystara, Birthright, and probably others that I missed. The Wheel of the Planes is also back, which I like.
Speaking of appendices, there's an Appendix E that gives an extensive "inspirational reading" list. There are some works in there you'd expect to see, like Fafhrd and the Gray Mouser, ERB's Pellucidar series, and Conan, but some more modern works like The Book of the New Sun and A Song of Ice and Fire. (In a particularly recursive move, Andre Norton's Quag Keep is listed, which is weird because it was itself based on the D&D game...).
All in all, a very impressive work, and my cautious optimism about 5th Edition seems to have been justified. I'll delve more deeply into the rules themselves in some follow-up posts, and there will be some more Greyhawk-specific material as the months wear on, but I can say that WotC seems to have struck the right tone and content for me with this one. Well done.