Several critics have also accused it of exaggerating its ability to match cheats with one another, chronicling its alleged failings on websites such as
Few other dating sites have provoked such a public backlash.
In countries and cultures in which arranged marriages are common, sites such as India's Shaadi and Bharat Matrimony, which boast many millions of clients, are a big hit with young people who want to influence how their marriage partners are chosen.
And a number of sizeable digital matchmakers, including Jiayuan and Zhenai, have risen to prominence in China.
One is its ability to create large pools of potential partners that would be hard to replicate in the real world.
Academics who have studied the industry believe that it and other forms of electronic communication such as e-mail and social networks are starting to have a significant effect on the ways in which people find love.
Vampire lovers can sink their teeth into the profiles on offer at Vampire Passions, while those obsessed with i Pads and i Phones can hunt for their i Beloveds at Cupidtino, a dating site for fans of Apple's products.
The rise of these and other dating sites has been driven by several trends in society.
“The period between New Year's Day and Valentine's Day is our busiest six weeks of the year,” explains Sam Yagan, the boss of Ok Cupid, a big American dating site.
Once seen as the last resort for a bunch of lonely geeks, online-dating services have gradually shed much of the stigma formerly associated with them.