In today's fast paced world it's easy to be quickly forgotten if you don't keep up with constant change.
An important part of marketing your work is staying up to date. If you're promoting your book or trying to promote yourself as a freelance writer you need to present yourself as an authority on the subject areas you write about.
Make sure that you keep up to date with the latest news in your subject areas and that you stay active on any forums or message boards that you belong to. Make regular blog postings to keep your audience reading and update your website frequently to keep people coming back for new content.
If you send out press releases or media kits, make sure that you update them to include information about your latest accomplishments, appearances, or clippings of your most recent articles.