Here is the release overview presentation with screenshots highlighting the important features and functionalities introduced in Salesforce Spring 16 Release

For videos, release notes and other resources on Winter 16, please navigate to URL http://www.salesforce.com/customer-resources/releases/spring16/

And here is the link to some great blogs summarizing the useful features in Spring 16 release

And here is the list of past release overview decks

  1. Salesforce Winter 16 Release Overview with Screenshots
  2. Salesforce Summer 15 Release Overview with Screenshots
  3. Salesforce Spring 15 Release Overview with Screenshots
  4. Salesforce Winter 15 Release Overview with Screenshots