The entire process with ConocoPhillips was incredibly pleasant and quick - I was never wondering what the next steps were. I met them at first on campus at a career fair, where they told me all about the world of IT and ConocoPhillips. I gave them my resume, and they quickly contacted me for an on-campus interview. Before the interview, they invited me to a wonderful dinner, where I got to know the recruiters and other possible new hires.
The on-campus interview was completely behavioral, and it was relaxed and comfortable. I talked to two interviewers simultaneously for about 45 minutes, and they were both professional and friendly. They left me with instructions to wait for communication in the next two weeks - it came, as promised, in a timely fashion. They invited me for an on-site interview.
I drove to Bartlesville and all expenses were paid, from the gas to the hotel to all the food I could hope for. It was a wonderful experience. The day of the interview we split up into two groups - half of us toured through Bartlesville while the other half interviewed, and then we switched. I met with three interviewers individually for about 45 minutes each, and we rotated. Again, the questions were almost exclusively behavioral - I was never asked to write any code or demonstrate knowledge, only to talk about my past experiences and how I made decisions in certain situations.
I ended up going with a different offer since Bartlesville, OK is not a particularly interesting location, but it was still a great experience and I'd recommend ConocoPhillips to anybody.