Social networking sites are fine in that it “expands” your social sphere and allows you to “meet” new friends but I prefer not to join any.
It’s reeking with privacy issues. Yes, it makes meeting new friends easier but it also makes stalking you easier. Take that from a self-confessed web stalker (just kidding!)
It’s a fad (the most dominant or “in” service changes every few months) and a waste of time to maintain. Friendster, MySpace, Yahoo 360o, whatever. They’re basically incompatible with one another, each duplicating many of each other’s functions, especially the basic ones. You have to create a profile on each with practically the same information. And when a new service comes in and a friend tags *ahem* you, you need to do it again. When something changes in one site e.g. adding a photo or a friend, the change does not propagate to other services. This is very inefficient!
Someone should really create a way to integrate this kind of sites. Perhaps, W3C can create a new standard.
But before that happens, here’s a more important point: the Web itself is like a big social networking site. You can create your own webpage or profile or whatever you call it in those sites and link it to your friend’s. Since you control the site, that’s less of privacy issues. In fact, this is one of Tim Berners-Lee’s vision when he created the Web. With the emergence of very user-friendly blogging software and dirt cheap or free web hosting, this scenario becomes more feasible.