It's coming. You know it. You dread it. Soon, the Web and 3D HDTV will merge. Someday, sooner or later, Wikipedia, and all things Wiki, will have to convert the bulk of their images to a three-dimensional format, or be left behind by all those commercial sites with 3D formats already created and available as vivid, 3D stills and moving images. Yes, yes it is that bad. See Wikipedia:3D television, Wikipedia:Smart TV. Expect this to converge, standardize, and then as prices come down, 3D images across the Web should become the norm.
Another reason to start even sooner is to create a hybrid 2D/3D system of images for display on either type of monitor. I imagine that that is more work than 3D alone.