I wondered what you think of the practice of publishing novel excerpts as short stories in literary or popular magazines -- do you think this is helpful marketing -- do agents or publishers take more of an interest if this has been done?
In my opinion, this can rarely be a bad thing, as long as you read and reread the rights that you're granting the magazine. (I.e., you don't want to sign away ANY rights that hinder you from publishing the book in its entirety elsewhere.) Look, agents get hundreds of queries a week, so if they get yours, and it reads "My Genius Novel was excerpted in Zoetrope," you can bet your bootie that it's going to make your query stand out. Why wouldn't it? It also reassures agents that someone else thought your stuff was top-notch, and no agent wants to miss out on the opportunity to find the next diamond in the slush.
Of course, whether it's worth spending your time submitting to these magazines rather than fine-tuning your ms or your query letter is a subjective call, but if you want to, I say " go for it."