For those unfamiliar with Groupon, here is the skinny: Groupon offers customers discounts on products and services in which Groupon has negotiated with the business for discounts based on an agreed upon number of people accepting the offer. They offer 1 deal per day, per city and then market this deal to the members in that market. They currently have over 33 million subscribers.
Groupon collects a 50% commission on sales from the business for each offer BUT, since they only offered one deal per day, the exposure was fantastic since everybody saw it. It didn't get "lost in the crowd". It was still a VERY steep cost but the advantage businesses have found from utilizing Groupon in their marketing efforts is from attracting NEW customers and focusing on customer retention.
With the launch of Groupon Stores, businesses can set up their own Groupon distribution presence and offer (and control) their own discounts. There is still a commission but it has been drastically reduced to only 10% of sales.
Groupon is promoting several features of it's new stores:
This could be leveraged well in your service department by running oil change specials, tire deals, etc. It would give your dealership the exposure through Groupon via the free business-specific page they'll provide.
This new page will probably offer your dealership some SEO value as well but my advice would be to not set up a page if you don't plan to offer any discounts. Too many dealerships have "Specials" pages on their own website that don't have any specials on them. Don't compound that huge mistake by participating in more "deal" websites in which you don't have any deals.
The biggest benefit to utilizing Groupon's Store is that they will market it to their members in your area through both e-mail and via the other announced new feature - the Deal Feed, which is sort of like a Facebook wall for consumers to see the deals offered in their area as well as deals offered from businesses they "follow". This does come at a cost (10% of sales from the offered deal) but the marketing power to attract new customers is huge.
With the rumor-mill steadily increasing that Google is going to buy Groupon, I wouldn't be surprised to see Groupon deals integrated into Google Place Pages. This would increase the perceived value of Google Place Pages to consumers in that it would centralize a single page in which consumers can get business information, see business reviews and see what deals the merchant is currently offering.
The new feature rolls out today in a few markets but will be available shortly to everyone.