I've been seeing nothing but the traditional "prop" type blades for use on the wind gennies and i dont really see why. If I ever get the time I am planning on trying a vertical turbine on a small shaft. something i've seen in numerous scifi films and books.
it seems like that would save alot of engineering. it would be omni-directional (no need for a tail fin), the generator would be in a fixed position (no need for brush slide power connection) being an apparently solid object the danger to birds and bats would be reduced (one of the main factors the wind industry is facing here in the USA right now) and the biggest thing (at least to me) the blades wouldnt have to be painstakingly carved and shaped.
nearly any matterial could be used for the blades, as both ends would securely anchored. something as light as nylon cloth or as heavy as steel sheeting. I saw a design by an austrailian fellow that used halves of 50 gallon steel drums to power his vertical wind pump. granted, that heavy of a design would not make a good electric generator directly attached to the rotor but using a gear/pulley system it could be doable.
there alot of things to consider with this design, obviously, but I think it has some serious potential.