The main new features include:
Content Staging and Preview
Now you can easily stage, preview, and schedule a wide range of new content, including updates to products, categories, and promotions.
Improved checkout experience
PayPal In-context Checkout increases conversion rates by enabling shoppers to pay with PayPal without ever leaving your site. Securely storing credit card information through PayPal Saved Credit Cards means fewer security headaches, and more frequent purchases.
Better built-in search
Enterprise Edition 2.1 now uses Elasticsearch. This search engine supports 33 languages out-of-the-box and lets you set ‘stop words’, search synonyms, and attribute weighting to deliver highly relevant search results. It’s also designed to handle large catalogues and configuring Elasticsearch is much easier.
Better Admin Panel
A new Admin Panel search feature enables you to quickly find customer and order information. Search synonyms are much easier to set up across multiple sites. Redesigned forms simplify and speed the process of creating new products, content, and categories.
Read Magento's full article here...