One of the most important things that you can do is KEEP CURRENT. My last web site was 2 years old and it lacked many of my most recent work to date.
By creating a new site, I was able to:
Send out a news blast to all my accounts ( a good way to keep my name in front of them.. perhaps generate some new business).
Showcase my new work.
Take advantage of some new tricks in web design that I've learned over the past 2 years.
Take a look at your web site.
Does it show the wide range of work that you do?
Does it communicate how you tackle projects?
Is it flexible enough so you can add new samples of your work?
Is it fast loading?
Look at your site as though you are the prospective client: Are you communicating your work to the best of your abilities?
Bottom line... don't rest on your laurels... keep your site fresh and new to attract new business.