I think in less than 3 years the Online Dating Market will divide into two well-identified branches.
13-25 years old persons (teenagers) not interested in serious dating; they will use the service for fun, sometimes merged with social networks, like Facebook dating applications. Teenagers are used to send a lot of emails, photos, videos, or simply stay in chat rooms for hours. They will need exclusive CONTENTS for members. They will want to be 24hs a day online or pending of their cellphone / smartphone / netbook or other computer.
Each person will have its private Truman Show. Everybody will be Truman for 5,000 "friends" (casual acquaintances / fans).
Mobile applications will serve as a complement to leverage those fun sites.
26-and more years old persons interested in serious dating. They will need quality CONTACTS (compatible real persons) like the ones provided by actual off line dating proposals, reliability, Code of Ethics, Legislation and Special Services (professionalism): the next generation of serious dating will be more scientific than ever, most probably the 16PF5 test for personality profiling in different languages (or similar test) will be a "must have" in compatibility matching.
An over 26 years old single who wants "compatible real quality contacts" needs professionalism / scientific matching techniques and allowing friends / parents / neighbours / relatives / fans or other social networking users to be involved in a private matter as building a personal relationship with future in mind will add an "interested third parties ingredient" in a process that only concerns two persons.