According to Joystiq, Nintendo said that it would being offering demos for WiiWare games at its recent investor Q&A.
President Satoru Iwata said it would dip a toe in the water by offering a small selection of demos this month. He didn't discuss regions, so it would be safe to assume this is only happening in Japan for now.
He hoped it would bring more passing traffic to the Wii Shop Channel, but nonetheless said he still doubted demos' effectiveness as a promotional tool. Let's hope the Japanese public proves him wrong.