I have tried it for the past few weeks and it has potential to be great. I think it has some good ideas. The problem is that a lot of people who are not computer people or techie will not switch because it took them a while to finally join facebook. Google has done some great things in its lifespan but social networking has always been its short coming (they did try it two times before with google wave and google buzz). I like to hope it because something. The "invite only" system is just being used to get interest into it. They want people to want it. As soon as more people get into it, it will get more attention.