By Olga Kharif
MOBILE ACTION. Moreover, because these sites attract people with common interests, the situation can be more conducive to a match. And much of the e-dating category's traffic increase over the past year came from social-networking sites, says Hitwise's Tancer.
Younger users tend to gravitate to social-networking sites, rather than to traditional e-dating enterprises, which typically serve 25- to 35-year olds. But that demographic profile could change. Though youthful users are often the early adopters of new technologies, their older brothers and sisters often follow suit.
Yet another competitive threat -- from mobile devices -- is brewin