Presumably there are some googlers around here that can explain the difference in detail,but Fei Fei Li is R&D in Google Cloud whereas Jeff Dean is taking the o

Presumably there are some googlers around here that can explain the difference in detail,but Fei Fei Li is R&D in Google Cloud whereas Jeff Dean is taking the organisational role as head of AI. So much more of the organisation will be involved - some product development, marketing, operations etc. as well a R&D.