Facebook has recently crossed 700 million users mark and it is growing by day. There seems to be no end as of now for such remarkable growth for Zuckerburg's company. Facebook has grown tremendously over the years and terms friend-unfriend have gone on to be so casual that people are using it in their normal life as well.
Well leave the Facebook terms aside for now, only thing I started this post with mention of Facebook is because they have got competition in the name of Google+. Google+ has received warm welcome by users and people are OK with trying it. Not to forget that they are still in close beta (or whatever) it is. So we can say Google+ at least has managed to start on good note which many other social networking sites even failed to achieve.