wood has been used for 1000's of years with quite good results. I'd say it'll be around for a while yet. Micarta is great, if you like synthetics, it's difficult to beat from a purely practical point of view. But Arizona desert ironwood is exceptionally dense, very hard and absolutely stunning to look at....
Dont forget, you can have virtually any wood stabalised. That means an synthetic resin is forced into the pores of the wood under vaccuum. It renders the wood totally waterproof, completely stable and very hard.