True that, particularly on the meaningful conversation side of things. Like many, I initially approached G+ as a kind of Facebook. I focused on basically friends, coworkers, acquaintances - personal relationships developed through assorted means. That was neat in having a replacement for my Facebook account, but I kept on hearing about noteworthy commentary being posted via links to G+ on hn, reddit, etc so I started exploring with new non-friend circles.

After branching out to my immediate interest areas (tech), a little later I ended up adding Philip Plait (bad astronomy guy), Fraser Cain and other sciencey/astronomy folks. The amazing Hangouts that these folks do a number of times/week makes me feel really lucky to have access to such a resource. Certainly having some degree of access to experts in assorted fields is nothing new thanks to the internets, but G+ has, in my view, made such interactions far more accessible.

I can only imagine that there are other groups doing awesome things with G+ who I have not yet found.