I tried it very briefly but I started to hate it during the registration process and never actually used it!
First problem, it won't let you use an alias as your user name - for example, I've used ffutures (short for Forgotten Futures) on Livejournal, Dreamwidth, etc. but that isn't acceptable to Google+
Once you create an account it then starts to try to mine your address book (if you use gmail, not sure if it's possible to join without a gmail account) and suggest your contacts as members of your "circle." Now I don't know about anyone else, but my email contacts include quite a few people and organisations I do not wish to have as friends.
It also tries to make a lot of your details public as its default - you have to switch off all sorts of things that are off by default at most other sites, e.g. your age, sex, email address, etc.
Maybe I was unlucky, but within minutes I was almost instantly spammed by dozens of "add me to your circle" messages. I do not believe that real people are so interested in reading my blog.
At this point I decided that enough was enough and closed down the Google+ account - and finding out how to do so isn't easy - and for good measure shut down a couple of other accounts associated with Gmail which I wasn't using. I think it will be a LONG time before I even think about using Google+ again.
