Groupon, which offers daily deals on food and entertainment in major cities, today launched Personalized Deals, a service that tailors each subscriber’s stream of daily deals to their personal preferences and buying history.

Personalized Deals are available in Chicago, San Francisco, San Jose, Los Angeles, New York and Seattle, and are slated to launch across Groupon’s more than 80 North American markets over the next few months.

Each Groupon subscriber’s deals will become more relevant over time as consumers share more information with Groupon and form buying patterns, the company says. Subscribers won’t see any changes in their Groupon interface. They’ll still receive a deal per day via e-mail, available for at least 24 hours.

“The number one request from our customers is for more relevant deals,” says Andrew Mason, Groupon’s founder and CEO. “After six months of product development, we’re excited to deliver. This is the biggest thing we’ve ever done, and we think one day people will think of the original, non-personalized version of Groupon the way we think of the steam engine.”

Customizing deals allows Groupon to run more promotions for businesses that are located outside of city centers, that cater to niche audiences, or that aren’t seeking the heavy volume traditional Groupon typically delivers, Groupon says. Sending tailored deals also helps address the overwhelming demand from merchants to be featured on Groupon, the company says.

“Interest in Groupon is so high we can only feature one out of eight businesses that contact us,” Mason says. “Personalized Deals opens Groupon up to more merchants who, until now, have been forced to look elsewhere to find new customers.”

Groupon says it has 11 million subscribers in 22 countries and hundreds of cities.