One of Google's Ranking Factors is popularity. The more internet users who Link, Pin, Upvote, and talk about your website the more Google trusts that your site is the real deal.
An additional benefit of social bookmarking and liking is websites that track "trending" links. These sites post your link, are indexed by Google, they get copied by other websites (scraper sites) and now you have a whole new set of links pointing to your website.
The problem with popularity is that a "Google Dance" can occure. A Google Dance is where you go up and down in the rankings, sometimes daily. To prevent a Google Dance you need to have a sufficient number of incoming links to your website. These links will help your website maintain it's position as it is trending. Without a good number of incoming links, your site is very might only rise to the top to fall down to the bottom of the first page or top of the second page.
I would suggest to ask your customers to "like" your site by giving them a list of sites where they can socially bookmark it and if they are willing leave testimonials on sites like Yelp which has the same affect as social bookmarking.
It is good to not communicate to every customer that you have to do these things to help you out all at once. It is better to spread it out over several weeks because you will not be able to carry the momentum and Google will think your site was a sort of "Flash in the pan" here today, gone tomorrow. Better to achieve stability then quick but short rankings.
Social Bookmark Sites
Plus many others that you can find searching Google.