Google+ is a social networking service from Google. The project is currently in limited release, and you must receive an invitation from Google or another Google+ member in order to join. The idea is pretty similar to other social networking services, but Google attempts to differentiate Google+ by allowing more transparency in who you share with and how you interact. It also integrates all Google services and displays a new Google+ menu bar on other Google services when you're logged into a Google account.
Google+ will make use of the Google search engine, existing Google Profiles, and the +1 button. Google+ new components include Circles, Huddle, Hangouts, and Sparks.
Circles is just a way of setting up personalized social circles, whether they be centered around work or personal activities. Rather than share all updates with an audience of hundreds or thousands, the service aims to personalize sharing with smaller groups. This is a feature already available in Facebook, though many users may just not know how to use it. Google+ users can also make public feeds visible to everyone (even those without accounts) and open to comments from other Google+ users.
Huddle is a group chat for phones. Rather than individually sending SMS messages, Huddle can pool them together to make a group chat which is still private to outside viewers, unlike Twitter.
Hangouts is just video chat and instant messaging. You know, the thing you can already do with Google Talk, Skype, or Qik. The point Google+ seems to be making is that you don't always want to be available for chat, so when you step into a "hangout," you're signalling your availability. This is only slightly more nuanced than simply switching your availability on or off or using Facebook to filter off chat invitations from unwanted "friends." With Hangout, you can signal availability to some or all of your circles.
Hangouts also allow group chats with text or video for up to ten users. This is also not a feature unique to Google+, but the implementation is easier to use than it is on many comperable products. Hangout use is only available on the Web version of Google + currently and requires you to install a browser plugin.
Sparks is a suggestion engine that finds interesting Web items based on your interests. You can pick from categories of interest and share items you find with others in your stream.
Instant Uploads is just an uploading app for your phone's camera. It instantly uploads any photos or videos to a private album that you can selectively share with friends.
Google+ allows location check-in from your phone. It integrates with Latitude check-ins. This is similar to Facebook or other social app location check-ins.
Google+ Chances for Success and Potential Pitfalls
Other than group SMS chat, there's not much new or innovative in Google+. However, early interest in Google+ has been strong. Larry Page, Google's CEO, announced the service had over 10 million users just two weeks after launch. Google has been behind the times in social products, and this product is late to the party. They've failed to see where the market was going, lost innovative employees, or let promising products languish while start-ups from other companies thrived (some of which were founded by former Google employees.)
Like other Google social projects, Google+ may also suffer from Google's dogfood problem. Google likes to use their own products in order to know how well they work, and they encourage their engineers to fix problems they find rather than relying on someone else to do it. This is good practice, and it works particularly well on products like Gmail and Chrome.
However, in social products, they've really got to expand this circle. Google Buzz suffered privacy problems due in part to a problem that didn't exist for Google employees - it wasn't a mystery who they'd been emailing, so it didn't occur to them that other people might not want to automatically friend their frequent email contacts. The other problem is that although Google employees come from all over the world, they're almost all straight-A students with a highly technical background who share similar social circles. They're not your semi-computer literate grandmother, your neighbor, or a gaggle of teens. Opening Google+ testing to users outside the company could solve the problem and result in a much better product.
Google is also pretty impatient when it comes to product growth. Google Wave sounded amazing when tested in-house, but the system broke when it expanded rapidly with hyped up demand, and users found the new interface to be confusing. That said, it could still have been amazing if Google had just let it grow slowly and organically.
Getting an Invitation
Google+ is available on the Web at http://plus.google.com, and there are links to downloading a Plus app for Android. As of this writing, you still need an invitation in order to actually use the service, and invitations have been periodically opened and closed depending on the demand. If you sign up for the waiting list, you should receive an invitation in the future.
There was a temporary loophole in invites that has been closed. You used to be able to tag a non-Google+ member in a photo or share an item with them in order to deliver a back-door invitation. Google reprogrammed this to give them a link to the item by email only instead of sending an invitation to the service.
When Google originally released Gmail and Orkut, users were given invitations that they could use to invite their friends, and only users with invitations were allowed to use the service. Google Wave used a hybrid of invitations and waiting lists.