Very often on Google+, I feel like I can hear the echoes in the valley walls. As for the actual product, once it gains traction it will be awesome, I think. The concept of circles is, I think, revolutionary. Yes, you can do the same thing with Facebook groups. But how many people do you know that have actually done so? Google just makes this so easy, and front and center to the entire user experience, that it forces you to do it and think about what you're doing (though I do have to admit to dropping most everyone in the "Friends" circle, and I think lots of other people probably do the same). You can define as many circles as you
There's also the concept (that I haven't tried yet for lack of equipment - but I might go buy a webcam after posting this) of a "hangout" which I think is basically enhanced group video conferencing, but not having used it, I really can't comment on how good or bad it is.
For all of you Android phone users, there is a native Google+ app, which is very well integrated into the Android user interface - you'll see Google+ show up as an intent provider all over the place (i.e. when you share stuff, Google+ shows up as a place that you can do that). Also, optionally, all video and camera operations on the device will be automatically uploaded to a private Picasa album (which I think is pretty cool).
I'm not sure how the invite situation is working out, but if you're not on Google+ and want to be, let me know and I'll see what I can do!