I have not been reading a lot of slush lately thanks to the Interns, so I don't have any words of wisdom that I've garnered from my pile. However, I took home a tidy little pile of slush today, so I hope to have more soon. But, never fear. I'm not the only editor out there bemoaning the writing issues we find in slush. Brooklyn Arden, best known as the American editor of the Harry Potters, and generally known as all around excellent editor, has a very instructive post here. I endorse and agree with every one of her points. Take them to heart. She knows what she's talking about.
Thanks to Fuse #8 for the heads up on the link.