Each year when I update the market guide, I begin to notice some trends as far as what changes editors seem to be asking for as far as their dealings with authors. This year was no exception. We have reached the point where the majority of the editors prefer e-mail submissions--although they still have their preferences. Some want the material sent as an attachment, while others prefer the material be included in the body of the e-mail. The market guide will tell you which--and they expect you to do as asked.
One new trend I've noticed this year, is that many more publishers are asking that electronic submissions be made only through a form provided on their Website. They all seem to be working against the onslaught of spam by taking more control of the submissions that come to them. Using the form also separates your submission from all the other e-mails that arrive in their box.
One overarching trend seems to be that publishers, more than ever, expect writers to abide by their guidelines. The consensus seems to be that if an author can't follow the rules they will dismiss you and your ideas out of hand. Never try to submit to a publisher without carefully studying those guidelines--and seeing a sample copy or their catalog.
I've also been watching what's happening with e-books. I've expected that the number of publishers producing e-books would grow each year, but at least for now, that growth seems stagnant.