From what I understand most new nursing programs
are not accredited in the few years or so. They must be up and running for at least that long before either of the NLN or AACN will grant them accredited status. We were told that when these organizations come in, they look at the curriculum, records of student performance, pass rates for the NCLEX, etc. This data can only be gathered by putting at least one class through the program.
As the previous poster stated, the program only has to be approved by the state Board of Nursing in order for you to be eligible for licensure.
If you are planning to attend graduate school (or go on for your BSN if enrolling in an ADN program), you might want to check with the schools you are interested in to find out how they handle this situation. That being, what happens if you graduate from a school that is not accredited at the time, but later gains accredited status?
As far as the difficulty of nursing classes vs normal college classes, I would say that they are comparable. The difference, in my experience, is that in the nursing classes you will be doing a lot more work for each credit. We had to write an inordinate number of papers in my BSN program, and this was in addition to clinical time (at 3 hours per week per credit) and the usual written and practical exams.
Overall most people don't have too much trouble in nursing programs if they have done well in their prerequisites, but it does require a significant time commitment. Those who struggled in my program were the ones with significant outside commitments such as work, children, etc. And most of them still managed to make it work and get through the program with decent grades.
If you have any questions, feel free to PM me.