Google has always evolved their various products in response to user feedback and usage data in order to improve the user experience and provide the right solutions, sometimes completely revamping or retiring products. Google+ is the most recent project to get a bit of an overhaul.
After talking to avid users, performing research, and analyzing data, Google decided to focus on what Google+ is actually used for and has unbundled some of the products that were tied to it, such as the photos, Hangouts and video sharing service. It also revamped the design with a mobile-first focus, recognizing where and how users are accessing G+.
Google promises to continue to evolve the product, scaling back on some features while optimizing others.
TechCrunch elaborates on many of these changes in a recent article and helps you understand your new profile and where the unbundled features ended up.