It was really easy. I got just a few questions about my previous experience and a few portfolio recommendations. The manager told me to add some user experience cases to my Behance profile. He was nice.

The interview process is pretty standard for a creative agency, it's more high level (since agency recruiters rarely have the depth of knowledge to ask deeper/technical questions). Overall they just try to ensure that you're a good human, personable and sound like you know what you're talking about. I met with a couple of people, reviewed my design portfolio with them, and generally described my background and what sorts of gigs I was interested in.