The Ring of Ghoulish Glee is the updated attack power ring. Interestingly, it doesn't seem to be the direct equivalent of anything in game, but is instead an item level 200 upgrade from the old Ring of Ghoulish Delight. It's the 50 Stamina that really makes the new ring interesting, especially for folks cruising various PvP avenues.
The Horseman's Seal is, of course, the upgrade to The Horseman's Signet Ring. Again, the Horseman's Seal is not a direct copy of anything in game. While that won't make it more attractive in and of itself, this "new gear" paradigm might open new gearing avenues to casual players. The Wicked Witch's Band is the other spell power drop from the Headless Horseman, an upgrade from the Witches Band. (Witches are 90% more wicked this year.)
Hailed as one of the finest items in the game, I still carry The Horseman's Helm with me so I can use that superfun laugh. Now, however, I get to sport the new The Horseman's Horrific Helm in instances. I'm warning the Horde of Shadow Council even now that I will kill any number of Alliance puppies to get my hands on that sucker. The hit rating on the Horrific Helm makes it a nice upgrade in slot -- it's got a little hit rating, without going overboard and mucking up the itemization. And, you can still use the item to cackle like a maniac.
The last item to get updated this year is The Horseman's Baleful Blade. Like last year's version, its stats are passable and acceptable, if not fantastic. However, its on use ability to summon swarms of pumpkin fighters make this item without equal in the "awesome style" department. The little fellows don't last long, and they're not likely to save the day in a boss fight. But, for Halloween flavor, they're the best thing in the game.
These upgrades are all pretty exciting, helping to keep the Horseman relevant even when we're getting ready to charge Icecrown Citadel. Good luck in your hunting, and wish me luck in mine.