Interviewing with Quantcast was very smooth. I first reached out to a recruiter through a friend, and she and I did an informational call in the fall. They didn't have any post-grad job offerings up at the moment, but she told me to get in touch in a few weeks. When I did, they informed me that they'd opened a Sales Planner position, and that I should apply.
I submitted my application online, and then went through three rounds of phone interviews. The first was with the college recruiter that I'd already been speaking with, the second was with a member of the sales team, and the third had three back-to-back rounds of half-hour calls with HR and sales people. The calls were different than other interviews I'd had, in that they asked very little about me - the vast majority of each call was set up to be me asking questions about Quantcast and the position. It was very conversational, and everybody I spoke to was super-nice, but the lack of questions from them did throw me off at first. The questions they did ask were behavioral and pretty standard - "What do you know about us?", "Why do you want to work in this industry?", etc... I got the sense that they were using the calls as a way to see if I would be a good fit culturally, and to see if I cared about the job enough to do research and come up with questions. There was no in-person interview.
Finally, about two weeks after the last interview, I received my offer and accepted it.