I can only speak to the orientation I had at Northeastern University. When we drove into Boston, my boyfriend thought orientation would be like HIS orientation at WPI many years ago - a casual come-in-when-you-want event that let you get your student ID badge, pick up packets of information, and so on. Instead, Northeastern's Orientation was a solid 2 hours of presentations in a structured environment.
We began in a medium sized orientation, with perhaps 12 large round tables holding 6-8 students each. They had a small buffet of fruit and cheese, as well as juices. They began with a promotional talk, discussing the features of the school. Then different individuals came up to give 10 minute talks on different topics. One woman spoke about the technical aspects of using the website - where to find your class schedules, where to locate your profile information. Another person talked about financial aid issues - how to apply for FASFA, how to handle loan requests, where to go for help with these topics. One woman talked about career services - how the office would help students write cover letters, tune resumes, and so on. Finally, after all of these talks were complete, we were broken out into smaller groups based on the type of degree we were interested in.
All of the undergraduates walked across campus to a more typical classroom. There were about 20 of us. I imagine the number was low because 1) it was spring term, so few people start schooling in the spring, and 2) this being an online system, most people don't bother coming in to a physical orientation meeting. I was the only Leadership person in the room. There was a mix of ages. Some were in their 20s, but others were in their 40s. The three "seminar leaders" for this part talked about different aspects of getting a degree online, and answered questions. We learned how to get our book lists and how to get the books in time, how to handle classes that were canceled due to low enrollment, and so on.
It was a haul to go into Boston (especially during rush hour!!) and it made very clear to me that I would NEVER want to go in for actual on-ground classes (which is what they call "in person" classes). I am very happy with my decision to do online only. I was glad I went for this orientation, though. It was good - at least once - to see the campus and the teachers and so on, to make that connection with a school which will be all virtual. It was also good to be able to ask questions to a real person and get quick answers. Finally, somehow I was under the mistaken impression that my classes started on April 15th. They really start on April 12th!! So that was of course important to know, so that I did not fall behind before I'd even begun.
All said, if you have the chance to attend an orientation with your school, definitely take advantage of it. You never know which tidbit will be very helpful to you.