I'm on there (as you know, since you just added me). I like the interface design and the way it handles friending/following people.
I'd happily ditch Facebook in favour of Google+ -- I never really liked Facebook, anyway -- but my non-techy friends haven't shown an interest in it. So just on that, I'd say it's got a way to go before it could be a Facebook "killer." I think it'll do well as "another" major social platform, though -- coexisting alongside Facebook, Twitter, and Tumblr.
My team at work got invites when it came out from the G+ devs (we do a lot of work with Google). So far I like it, the circles concept is cool but not unique (for example, Live Journal has had this feature for almost a decade). It's better than FB or Twitter, but that's because it allows a lot more freedom in posts and has a much smaller user base (no offense to FB but this actually helps).
It won't kill FB and that's fine. Facebook at this point is basically AOL, it's lowest common denominator. I'm guessing G+ will do well but it's not going to have 700 million users. And that's probably a good thing.
I agree that it's pretty good that not everyone's on there, but I would like to have some more people come and join the community because there isn't a lot of activity on it just yet. Also, I can't get my profile pic to show up for more than a minute after I set it. It just goes back to the blank icon. Haha
Depends who you tend to roll with. Most of my friends are techies so they're all on there and using it. The problem is they all just use it to share blog posts, videos, etc. So right now it feels like I'm just reading my friends RSS feeds.
My other big issue with it right now is the requirement of using your real name. I think this is rather silly and I see no reason for it. The bigger problem right now is people getting banned because they have weird names that Google thinks are fake (when indeed they're real).
As for your profile pic, Google relies heavily on caching of data, and it usually takes time for all of it to propagate out. My photo took several days to propagate everywhere.
You were right. My pic just showed up last time I checked G+. Anyway, I don't think it's too 'silly' that we use our real names because it's supposed to be competing with Facebook, but I do think it would be better for networking with people I don't know that I don't use my real name.