It is interesting to throw the question out there to the business owners. What do business owners think is most valuable when it comes to marketing their business on the Internet? Google consumer surveys is an amazing tool to launch interesting surveys and know about valuable trends from Internet users. Keepcustomer.com used Google Consumer Surveys to find how business owners plan to spend their money to get business from Internet--the results were fairly predictable--websites and word of mouth marketing stand out as the top areas of spending (at least that's what the business owners think).
It is interesting that more business owners in mid west region think that word of mouth is more important than everything else. Email marketing, SEO and social media and Reputation management are also important for businesses, but not a top priority it seems, and rightly so. Why you ask? The most important thing for any business is to get people to buy once they find the business online. Word of mouth and website are natural steps towards customer purchase. Customers like to read opinions about the products and services once they see the products on website (so having a website is very important).
Besides, it is easy to market word of mouth on your own website where you can publish the best reviews from your customers (It is the only place on the Internet where you are fully in control of your content). Assuming the reviews are an honest selection, people do tend to trust website reviews as much as reviews found elsewhere on the website.
As a business owner, what are you going to bet on? Word of mouth definitely seems to be safer.