I'm kinda curious though. In an interview about the Planar Handbook, Bruce R. Cordell said he was working on a product centered around a part in the back of the DMG that player's usually drool over. I guessed that this was a book about magic items, but it's nowhere to be found in the...
It was co-authored by Bruce R. Cordell and Gwendolyn F.M. Kestrel, it contains material that facilitates the incorporation of planar material in a campaign. It's a brown book, so it mostly targets players (though there must be some stuff for DMs). Considering the current trend at WotC, it will...