Here are the major enhancements introduced in the HDMI 1.4 specification:

• HDMI Ethernet Channel – Adds high-speed networking to an HDMI link, allowing users to take full advantage of their IP-enabled devices without a separate Ethernet cable. 

• Audio Return Channel – Allows an HDMI-connected TV with a built-in tuner to send audio data "upstream" to a surround audio system, eliminating the need for a separate audio cable. 

• 3D – Defines input/output protocols for major 3D video formats, paving the way for true 3D gaming and 3D home theater applications. 

• 4K Support – Enables video resolutions far beyond 1080p, supporting next-generation displays that will rival the Digital Cinema systems used in many commercial movie theatres. 

• Content Type – Real-time signaling of content types between display and source devices, enabling a TV to optimize picture settings based on content type 

• Additional Color Spaces – Adds support for additional color models used in digital photography and computer graphics.

• HDMI Micro Connector – A new, smaller connector for phones and other portable devices, supporting video resolutions up to 1080p. 

• Automotive Connection System – New cables and connectors for automotive video systems, designed to meet the unique demands of the motoring environment while delivering true HD quality.