Finally got my hands on the DMG II yesterday, and it was well worth the forty bucks I forked over for it.
My favorite bits from the book were:
1. The entire first chapter, which goes into detail on all the stuff that a DM has to deal with on a regular basis. I suspect that this was Robin Laws's major contribution to the project, and if so, he did a fantastic job.
2. The entire third chapter, including the primer on medieval society and law and punishment (which kicked off with a warning that made me grin), and the very cool section on magic events. My favorite magic event has got to be the Killing Frost of Ghulurak -- it's got a very Cthulhu feel to it that I absolutely love, and the image of this unnatural winter creeping in from the north, with all these evil critters coming in its wake, and covering the whole world over the passage of years is a very cool image that just won't leave my head.
3. Saltmarsh, which is a very well laid-out setting, with adventure hooks and locations laid out much like the locations of the Forgotten Realms Campaign Setting. I like this method of setting design, and I hope to use this scheme when I design my own setting.
4. The Unique Abilities and Sample Complex NPCs from the fifth chapter, which can make for some very memorable characters.
5. The entire sixth chapter, particularly the Students and Masters section, the section on Running a Business, which among other things outlines the adventure opportunities that can arise over the course of the characters' career in his chosen venture; and the section on PC Organizations, the Shining Crusade in particular, whose code best fits my vision of the code that a paladin would follow.
6. I particularly loved the Bonded Magic Items section of the seventh chapter, which allows a PC to turn a masterwork item into a magical item without being a spellcaster or having to have a spellcaster enchant it, but by investing his own inner power into the item through an exacting bonding ritual. I've been kicking around the idea of a warrior who forges his own signature weapon and invests it with his own power for quite some time, and something like this is an absolute godsend.
7. The Magical Locations section of the same chapter is another favorite, allowing for some very cool scenes with the added bonus of granting PCs some cool magical powers that last for a good duration without being permanent.
8. The Weapon and Armor Special Abilities, some of which are quite powerful and can only be used a certain number of times a day, and the Weapon and Armor Templates, which are some very flavorful stuff in general that's definitely going to see use.
9. And finally, the section on artifacts is a good closer to the book. Far from being just another list of artifacts like in other D&D supplements, it goes into detail on how to introduce them, how to get them out of PC hands once they've served their purpose, and my favorite bit from that section, the listing of ways to bring about an artifact's destruction and the meanings behind them.