I've often described TPMtoday as the world's first and only blog dealing with trade promotion marketing. I'm going to have to change the description, though -- Multi-Ad has launched a blog recently called The Co-op Connection, and when I visited it I found a link to another blog called Co-op Queen Buzz, which has been around for almost a year. I'll have to drop the "only".
Both look interesting, especially for those involved in media sales.
If anybody knows of other blogs relating to trade promotion, co-op/mdf, or other channel management subjects, please let me know, and I'll pass on the word.