I don't believe in writer's block. Put me in front of a keyboard and I can write.
But, because I spend my life sitting at a keyboard--writing and editing and creating page layouts, Web sites, and advertising material, and doing other related tasks, and because a good portion of my social interaction comes via e-mail and Yahoo groups and blogs--I sometimes get "writer's disinterest."
Writer's disinterest might best be defined as: I can write; I just don't want to.
I want to be somewhere else doing something else.
So I usually do. I find something else to do until I either must return to the keyboard because of a client- or editor-imposed deadline to meet or I want to return to the keyboard because inspiration struck.
Writer's disinterest doesn't strike often, never lasts long, and is easily cured.