Once people get over the idea that CGI = better movie, I think 2D will make a comeback. In fact, I think we're already seeing a growing discontent with the CGI talking animal "funny for adults too" style, among critics if not among kids.
Okay, just calm down. It's actually a fairly accurate statement, because most CGI movies (at least the type we're talking about) are in fact rendered via 3-dimensional computer models. Whereas a "2D" movie is rendered as 2-dimensional images. It's confusing because those images could convey three dimensions, but those dimensions don't really exist -- whereas in CGI those dimensions do exist, but the end result is in fact still shown as a 2D image. And then there's the whole issue of using CGI to make movies that don't use 3D models, like Flash stuff, where perhaps there wouldn't technically be anything drawn by hand. (Though usually, there sort of is.)
Sooooo I'm still not 100% sure of the correct terminology, but "2D" seems good enough. Meaning there may be perspective but it is not fully rendered.