Have a look at Google+, I think unless people have a decent set of their friends on the service as soon as they join they are going to quickly lose interest. F

Have a look at Google+, I think unless people have a decent set of their friends on the service as soon as they join they are going to quickly lose interest. Facebook has set a high bar as for lots of people they can find everyone they know. Any competing service will need to match this as well as possible with crazy early growth.