More than the PAB accreditation, I wouldn't recommend online programs for planning school in general unless you're already working in the field and trying to get your degree at the same time as a non-traditional student. Planning school usually involves a lot of group projects, presentations, community outreach, possible studio classes, and specialized computer programs
- all of which don't lend themselves particularly well to an online program.
Then again I wouldn't recommend planning in general for undergrad either a whole different set of reasons...but again this depends on if you're 17 year old going to college for the first time or if you're 40 and going back for your degree. Can you tell us more about your background?