I was called in for an interview shortly after an employee submitted my name as a referral. Prior to that, I had applied to a position on the company website a month or more earlier and heard nothing. Having a referral from someone who can speak to your qualities and from someone who is equally respected by those interviewing is a must.
The majority of HR personnel are located out of the Highlands Ranch, CO office. As of the end of 2011, the Syracuse office no longer has any HR rep. When interviewing, you'll meet the receptionist and then meet directly with hiring scientists/engineers/managers. Typically you'll meet with a few different people from different work groups and experience levels. My interview was a full-day process from morning until late afternoon. I met with over a dozen people one-on-one in what must have been every business unit. My head was spinning at the end of the day and I was really happy to have had a big breakfast and coffee beforehand. I'd suggest oatmeal or something that will provide sustaining energy. I think they are moving away from this interview method, though, due to complaints.
Make sure you like the people you interview with, because there's a 95% chance you'll be working directly with them. And, make sure you're open and honest about your background and experience. Not only do you want to make sure you work for a place that knows what you can and cannot do, but you also don't want to be put into a position and eventually disregarded if you didn't meet expectations. I would say to hold off on explaining your eventual career goals unless they match up with the position OR unless the body language of the interviewer expressed genuine interest.
The job offer came pretty quickly (only a couple of days after the interview). If they like you, they will jump to send you an offer -- mostly because they have an immediate need for you. At least in Syracuse, they don't normally hire people unless the need is immediate. I think they are trying to change this and move more toward planning for the future.