As usual, Editorial Anonymous's blog is full of great advice (and much hilarity). If you are an aspiring writer, or even a published one, this blog is required reading. EA is posting a very useful series called "Definitions for the Perplexed" where you can read about publishing terms such as C,M,Y,K or proofs or BookScan. Here's the most recent post, but make sure you scroll down to see the posts over the past few weeks. While you're there, make sure you check out EA's list of Things Not To Send in Slush Ever Again in the margin.
Also courtesy of EA is news of an virtual cat fight over the news that several agents twittered on why they were rejecting manuscripts. Follow the links, but if you want to cut to the chase, here are some of the Twitter posts. (From Chico Writer's Group.) Regardless of how you feel about the ethics, there is a lot of good advice in those tweets.