I keep seeing the term Easy Drive on newer SAR ADCs from Analog Devices.  What are the advantages of this new architecture and how does this help with signal chain design?

Easy Drive allows ADCs to be driven directly with precision amplifiers or signal conditioning stage, thus eliminating the need in many cases for a dedicated high speed ADC driver stage (that is typical in SAR ADC based designs).  With High-Z mode enabled, the cutoff frequency of the input RC filter (that helps remove more wideband noise coming from the upstream signal chain components) can be set lower than with traditional ADCs.