For years the “E” in eHarmony was a bit of a misnomer. Despite the company’s success online — the matchmaker says it is responsible for an average of 271 marriages a day —  it only recently started to seriously embrace the Internet. For much of eHarmony’s 10-year history, the web was merely a platform for distributing its compatibility survey and for letting customers scan matches.

Then it decided to hitch its business to predictive software, the technology used by sophisticated Internet companies such as Netflix (NFLX) and Google (GOOG). Under technology chief Joseph Essas, a former Yahoo (YHOO) search engineer, eHarmony has developed its own computer algorithms to optimize love connections. But there’s an added layer of complexity in applying the technology to dating. “It’s not just that you have to like the movie,” explains Essas, comparing his efforts to Netflix’s. “The movie has to like you back.”

Before Essas’s arrival two years ago, eHarmony analyzed a few dozen variables per user. Today its technology takes into account hundreds of different traits, including crucial information about how users behave — like time spent on the site or how long they take to respond to an e-mail about a match. The company collects this behavioral data and uses it to predict how users will respond to proposed matches. The site, for example, has found that Manhattanites are less willing than the general population to travel outside their immediate area to meet people, so eHarmony might not present matches beyond narrower geographical boundaries.

eHarmony, which charges $240 a year for its service, also has found that communication — e-mails, phone calls — is the best indicator of a couple meeting offline (and ultimately finding love). To further aid in sparking conversation, eHarmony has redesigned its “enhanced” profile pages (the ones featuring folks eHarmony deems right for you) to highlight common interests. That way, two people instantly know they share a passion for the Lakers or for cooking shows — two potential conversation starters.

CEO Greg Waldorf says the privately held company, which has an estimated $250 million in annual revenue, has doubled the size of its technology team, and he calls software innovation a top investment for the company as it enters its second decade. So far the results have been promising: eHarmony has seen a 10% increase in users communicating with their matches. “People are really discerning about what they want,” he says. “If you actually find someone worthwhile to talk to, we’ve done a pretty good job.” Sounds as if eHarmony is learning to love technology.