Almost every encounter in the various Essentials adventures has additional fantastic terrain. The only other traps/hazards are a Falling Portcullis Trap encountered towards the end of the DM Kit adventure.
The Rules Compendium has rules for Traps and Hazards, but none of the actual examples from the DM Book. It describes the same fantastic terrain, with the exclusion of slides, but does not include the information for scaling terrain effects to different tiers of play that is in the DM Book.
I sold my DMG a few months ago to remove some clutter and because I thought it was as junked as I knew the numbers in PHB1 and MM1 had become.
Well....in a way I was right, but the new Dungeon Master book in the Kit isn't all the DMG1 was. The new book reprints a lot of stuff from the DMG1 and the new Essentials Rules Compendium, but doesn't have that feeling of completeness that a DMG1 has.
IMO, if you are going after a new DMG book -- go for the DMG2. Great buy.
The other stuff in the Kit is pretty cool. It gives you tokens, a little terrain, and an adventure. Like Flobby said, you have to weight your options.