I am two classes away from completing my MBA through New York Institute of Technology's online school
Ellis College. All of the previous accreditation comments are valid. I chose Ellis because of their affiliation with NYIT, but they are attempting to break away and become an independent Ellis University. Classes are expensive, but my employer pays up to $6,000 in tuition each year. The thing I like most about the Ellis MBA program (not sure if undergrad is the same) is that all of the classes involve real-life scenarios. For example, in Accounting for Managers, you are asked to perform various tasks for a fictional company that a normal accountant would do. I have yet to take a test, which suits me fine because you never take tests in the real world and in college I used to cram for tests all the time which isn't conducive to retaining information. Most of the deliverables are 500-1500 word reports. Some have additional Excel spreadsheet attachments depending on the class (accounting, finance, etc.). I'd say the most difficult aspect is when you get a class that involves teamwork. The majority of the classes are composed of students in the continental U.S., but there are also some students from all around the world. It is difficult (but doable) to coordinate times to meet to discuss assignments when everybody has full-time jobs, especially when they're in different time zones or different continents. Then sometimes you get people in your group that just don't want to pull their weight. At the end of the class though you get to rate the performance and contributions of your fellow teammates, which becomes part of their grade.
Ellis College has an excellent online platform (how their classes are set up). Classes involve traditional readings from textbooks, online readings from their website, short online videos from professors at Columbia University, Chicago School of Business, and other highly respected institutions that contribute to the curriculum, real-time chats with fellow students in formats the entire class can see, just your team can see, or private chats with students one-on-one. There is also a bulletin board format similar to this to post questions/comments and have discussions. Some professors hold weekly chats with the class, others don't. But all are available to reply to discussion posts. As with any regular school, some professors are better than others.
Online classes have been a godsend for me. I just simply don't have the time to go to a brick-and-mortar school. I also work overnights so I get about 6-8 hrs of free time a night that I can work on assignments.
I don't know what other schools are like, but mine is self-paced with assignments usually due each Sunday night so you must be disciplined enough to do readings and work on your assignments throughout the week.
I generally think that traditional diplomas are more respected than online degrees, but then again I couldn't be obtaining my MBA now if I had to go to a traditional school. I made sure I chose a school that was affiliated with a respected brick-and-mortar school.