Disclaimer: I have just now gotten access to Google+, so this review is a reflection of other reviews, some personal experience, and a weary view of novelty.
Google+ is out in very limited test. Some small number of well connected people now have access to a new piece of social software from Google, and initial reviews have been generally positive.
How do you assess whether the initial reviews of a system designed for communications are accurate for when the system eventually gets rolled out to a wider audience? Consider that the first people into the system were hand picked, that they generally like getting access to new systems, and that they are relatively experienced and gregarious online experts. Certainly they will like something new that only they have access to – quite independent of the set of features – because it gives them a chance to reconnect to old online friends and make some new ones.
When a communications system becomes available to the general public, the system dynamics change greatly. The initial group of participants can all be presumed to be interesting to each other, so talking to any random individual is likely to be someone relatively near you in social circumstance. As the population explodes, the random person gets less and less interesting, to the limit of when the random person is likely to be a spammer.
Google+ is at the invention stage. Much like Facebook seeded its early use poll with Ivy League students, Google+ is doing its shakedown cruise with fans and friends and family in the first batch. Who wouldn't like to try out a new, expensive, mostly empty system and establish yourself in it? I'm waiting for the next round of invites, and hoping to enjoy it while it's in early growth stages and not when it's in long-in-the-tooth maintenance mode.
Edward Vielmetti's Wordpress weblog 
So far, my favorite thing about it is the on-the-fly redaction UI when you are submitting feedback (little “send feedback” widget in the lower right corner of the non-mobile site).
I agree with you 100%. The one thing I of hope will be different on Google+ is that the Circles will help preserve the “initial group of participants [who] can all be presumed to be interesting to each other” and scale to subsequent groups based on different criteria of interest.
The flood of general users is what basically killed Yahoo! Answers, and a few other communities. Mixing up the bowl of Superman ice cream is what kills growing communities