I applied online. I interviewed at Cell Press (Cambridge, MA) in Dec 2009
Interview
You must have an interest in being an editor. Once they have decided they are interested, you are given a test with two weeks to complete; mine consisted of coming up with a number of review ideas for a special reviews issue (I am a reviews editor), as well as coming up with individuals that would be appropriate for the editorial board for my journal. If they are happy with this, you are given a phone interview. I then had an in-office interview with a number of different editors, some of which were multiple at a time. I also had a short reading and abstract writing test in the office.
Interview questions [1]
Question 1
This isn't actually a question, but I felt like I needed to convince the individual who is now my manager that I was interested in being an editor rather than trying to find any job I could get after my postdoc.