I'm actually on G+ and I use it kind of a lot. I thought the discussion might benefit from somebody who's actually actively using the service rather than having sampled it and written it off as "I hate social networking and this is social networking". I'm enjoying it a good bit because it's more interactive and engaging than Twitter and with a lot more obvious and up-front control over everything than on Facebook.
The integration with Picasa is excellent and I'm looking forward to the (optional) integration with the other services. I'll really be happy with it when Gmail and Voice filters can use my Circles to do useful work, i.e. let family and friends through, dump the other crap.
I'm still using Twitter, mostly because I'm still following #FuckYouWashington, but less and less. G+ easily occupies the same space as Twitter and with a little tweaking will easily replace Facebook for me.
As for the supposed privacy issues, I haven't run into anything that concerns me. When I share something Public, I take for granted that means Public. When I post to a smaller Circle, I trust it go to that smaller Circle. If they want a more accurate profile of me to present ads which I might conceivably be interested in while I'm doing my friends-and-family socializing, that works fine by me. I've dismissed about a million Zynga ads on Facebook and their ad-bot code can't take a hint so more accurate ad profiling works in my favor by being less irritating by several orders of magnitude.
Moreover, I can use any pseudonym I like as long as I don't use it on G+ which seems a reasonable trade-off. If your concern is that the CIA might get grandma's cookie recipe, then you're screwed if your family is contacting you through G+ but hopefully you're bright enough to do anything truly nefarious on a more secure channel.
I follow a couple of Googlers, a couple of celebrities I was already following on Twitter and that's just about it for now until invites are opened a little wider. In all it's low-key and fosters a more interesting kind of correspondence. Open discourse seems to pop up a lot more often and it's a lot more coherent than either a Twitter discussion or a Facebook comment thread not to mention a lot easier to join a public thread.
In all, I like it a lot and I'm looking forward to the improvements.