Google+ debuted about a month ago. Despite a limited initial release, its user base has exploded. This isn't that surprising considering the prevalence of Google accounts already in use and the comfort most people now have with the idea of social networks.
Google+ has some characteristics of both Facebook and Twitter. Like Facebook, you can write posts of any length, share interesting finds online, post photographs and (video) chat. Like Twitter, two-way relationships are not required. For example, I follow the public Google+ posts of Randall Munroe (author of the xkcd webcomic), but since we don't know each other he's not following me back.
There are numerous guides to Google+ that go into great detail such as Mashable's Guide, so I won't do so here.
Two early Google+ controversies have arisen from Google's efforts to pin down user identities. Initially, Google+ required users to state their Gender (male, female, other) as public content. Some users chose other in order to maintain her/his privacy, but that led to some weirdness as you might expect. After user complaints, Google+ added privacy controls on this field although the field itself remains required.
Currently, there's considerable controversy over Google's "real names" policy and fairly ham-handed enforcement of it. danah boyd has an excellent post on the topic at apophenia, so again, I refer you there.
The reason I'm writing about Google+ at all is because I think that, over the long term, it could be a very powerful tool for academic social networking. Currently Google+ is only usable with regular, commercial Google accounts and not with domain accounts. Or, at least, not with the University of Minnesota's domain accounts. However, once it is available for the University's domain accounts, then students, faculty and staff will have a place to define a professional Google identity, make (more and better) use of Google's many powerful tools and network with each other in their professional context. As a professional tool, some of the problems that have cropped up so far with Google+ will be a little less acute. For example, the real names policy (as in, you have to use yours or else) makes more sense when you're at work than when you're on a social network for personal reasons. Google+ could serve as the gathering point for your work reading, writing, ruminating, mail and more without having to intrude on your personal identity.
However, Google+ isn't at this point yet. Right now, if you want to try it out, then you will have accept some risk. First of all, if you do use it for work posts, then you're connecting your personal and work identities. You will want to think about this carefully and use your circles judiciously. Second, you will have to pass muster on your name. Not only has Google aggressively pursued users who Google believes to be using pseudonyms, but it's even gone after actual users who happen to have common names. When it does, Google suspends access to _all_ Google products.
So, apart from idle curiosity, why bother? Well, in my case, I've used it as a place to write work-related posts which are too long for Twitter, but not worth a full blog post and which I want to share in a fully public sense (not an option on Facebook). If you already use Google Photos (aka Picasa), it's an easy place to share your photos. Indeed, if you have an Android device, it can be the easiest way to share photos from your device. If you really, really, really hate Facebook, then you might appreciate Google+ simple interface and absence of Farmville. You might also like the video chat.
I'll keep using Google+ because I like to play with new toys, but for most users, it will need to mature before it becomes a must-use tool. If you wish to, you can find me at amyewest.