I've always been curious at why people tend to prefer only certain types of driftwood for tanks (manzanita or mopani, for example). Looks, certainly, are a factor, and availability (manzanita grows in the US, out west). Though mopani is African, I believe, so I scratch my head there.
But as far as I can tell, any hardwood will do, especially if it's long dead, presoaked, and the bark has been stripped. That being said, a friend of mine (who worked for years at a nice lfs) refuses to purchase any sort of wood for his tanks. He's always been a fan of finding whatever looks good and dumping it in without any prep, and natural manzanita probably can't be found within 2000 miles of here.
I bought some mopani from F&S because it was fairly cheap and adding it to an existing order didn't increase shipping, but I stare out my window at the forest out back daily. Surely I can find some oak that looks good and won't destroy my tanks' ecosystems?