I will say this....blogs are a much better way (as of right now) to market whatever you may have to sell/ push/ whatever. Look at Clay Travis, every day he is pumping out new material on his blog and when his new book hits all these daily readers will be reminded he has a book coming out. He also has his older books listed.
Saying social media is the future and one and all being of the future of marketing is about as dumb as saying that they have no use in marketing. It's all a mix, baby. Use it all, track how people are finding out about you and go hard on what gets them there. If using word of mouth because you're damn good, so be it. If you have to do the social media thing a little more, so be it.