There are only rumors about a Kindle 4 (or there are people who want to believe there will be a Kindle 4), facts are that Amazon will/would like to bring 3 devices to the market, two tablets in 7" and 10" sizes (those will be definitely touch LCD devices) and one 9" device, which is the most mysterious at the moment. So if there will be an e-ink device, it could be the 9" variant. Amazon always kept their newest devices in secret until their announcement, we'll just have to wait