Now, a new survey of American households shows just how important this phenomenon has become: since 2005, a third of marriages were the result of online meetings, with nearly half of those coming through online dating services. The good news? Fewer relationships that started online ended up in divorce, and people were generally more satisfied with the ones that survived.

The numbers come from a survey sponsored by eHarmony, a dating site that frequently uses its advertisements to suggest that it makes matches based on psychologically validated personality profiles. …

All told, about a third of the marriages that occurred during that period arose from relationships that started online. A total of 45 percent of these came from online dating sites, 20 percent occurred through social networks, and another 10 percent came from chat rooms. Things like e-mail, blogs, and instant messaging all accounted for less than five percent of the relationships (online gaming came in at 3.6 percent). The real world was even more heavily fragmented: work and mutual friends accounted for 20 percent each of the introductions; school and social gatherings came in at around 10 percent each.