To my way of thinking, flannel and flannelette are really the same kind of brushed cotton. Flannelette was always the cheaper, thinner, slightly more stretchy version and did not wash and wear as long. Flannel was more expensive, had a tighter weave and behaved better in quilts. Flannelette seemed to come more in plain colours and baby and child prints while flannel was a little more "grown up".