I work with a bunch of them. A UX designer's basic job is to figure out how a product should work: who is the user, what do they want, how should they interact with the product, and how should the product's UI be laid out to accomplish that? They use a bunch of tools, from Macromedia Fireworks and Photoshop on the static side down to JavaScript and Python/PHP on the dynamic side. At Google at least, it's very common for UX designers to be able to code in rapid prototyping languages, though they usually know nothing about large-scale software engineering (beyond what engineers tell them).

A UX researcher's basic job is to figure out how users behave and what they want. This is basically applied social science. They work directly with users - sometimes through usability studies and one-way glass, sometimes through focus groups, sometimes through going out into the community and talking with people who use the product, and sometimes through logs analysis and quantitative data. This is not usually a technical position, but it requires someone with familiarity with the scientific method, a curiosity about people, and often good statistical/quantitative skills.

Since he's a UX lead, however, my guess is his day job came down to two things: hiring new UX people, and prioritizing requests for the skills of his reportees.