There's a few products on the list that I'll likely pick up or at least look at:
Player's Handbook II: I'm curious as what the racial advancements will be as well as if the new classes with be new or reprints from the Complete Series.
D&D Player's Kit: Since I'm currently reworking D20 to allow for quicker play (since I play Dungeon Bash mostly anymore), I'm curious to see what this will be like.
Fiendish Codex I: Hordes of the Abyss: I've liked the whole monster series, and since my games tend to have a lot of fiendish flavor this book will hopefully be a welcome addition to my collection.
Monster Manual IV: I'm always in the market for new creatures. Sure, I may not use even a quarter of the monsters in my library, but you never know when a new monster book will contain a new creature or new ideas that must be added into the game.
Secrets of Xen'drik: This is one of the most interesting sites in Eberron. With the new D&D Online game coming out this summer, it's a no-brainer to put out a book detailing the region. I may not outright buy this one, but I'll certainly look at it.
d20 Spectaculars: Silly title aside, I'll give this one a look see. If it works well with RPGObjects' Blood and Vigilance, I'll pick it up. If not, well, I have B&V and M&M 2E for my superhero gaming needs.
Tome of Battle: The Book of Nine Swords: I'll give this one a look. Not sure if I want more combat options, but it can never hurt to look. I'll likely buy it if the new classes are well-done.
I'll buy both of the Gargantuan dragons, as well as at least one case of both the Bounty Hunters and War of the Dragon Queen sets. I get more use out of minis these days anyway.
Kane