It's 2015 already and the most anticipated moment of the year is the release of Drupal 8, something the community has been working on and polishing for more than 3 years. As of Jan 4th, there still are 88 critical bugs remaining to the first Release Candidate, while everyone can download and test the latest .
As described in the Drupal 8 Official Page:
Drupal 8 Will Have Something for Everyone to Love
Drupal 8 will set a new standard for ease of use, while offering countless new ways to tailor and deploy your content to the Web. Easily customize data structures, listings, and pages, and take advantage of new capabilities for displaying data on mobile devices, building APIs, and adapting to multilingual needs.
With a leaner and meaner core, easier migration process from earlier versions, in-place content editing tools and loads more power for modules and themes thanks to a modern Object Oriented Programming (OOP) approach on the backend, there is something for everyone to love in Drupal 8. When will it be released? See the FAQ.
If you are interested in a fast read about it and got a complete "fast" idea of what Drupal 8 will deliver, you will only need a couple of minutes of your time to read this Drupal 8 Infographics made by the Drupal Association.
Additionally, and mostly for Theme Developers and site builders, we have created a small list of useful links: