Social sites are becoming more and more popular over the time. On one hand it is really a social helper that is used by every age group on the other hand it is becoming favorite place of spammers and advertisers. More check the beautiful post Social Media today. What is the future of these social media sites (Favorite resi. for spammers).
Your right - but they'll be more companies like twitter in the future and more spammers hanging on to them. It just comes w/ the territory.
Well not only social networking most kind of sites are attacked by spammers specially where we can post comments or do discussions.. its just the part of the game
I don't think that will kill them off. Blogs also get spammed by advertisers and yet blogs have yet to die down. That is just a fact of life with the internet.