Odds of Getting In
Those who love to write but aren't interested in wasting away as a struggling writer are pretty attracted to editing jobs, so there's some stiff competition. Be prepared to be awesome, or else have a little difficulty getting in the door.
Job opportunities for newspaper and magazine editors are going down; opportunities for those who are interested in or willing to work for Internet companies are going up. In all, the number of open positions shouldn't change that much in the coming decade, but the nature of your work environment might. It's okay though—you never really wanted to work in all the hustle and bustle of a writers' bullpen anyway.