CPR Today does not offer a legitimate online CPR certification. There is one online course through the American Heart Association -- however, if you do the online portion of the class, you still have to make an appointment with an instructor to do a hands-on skills evaluation before you can be certified.
BLS is Basic Life Support -- but it is more advanced than the CPR / AED class. This is the classes nurses need. The standard CPR / AED class is not enough. There is a difference in the protocals for healthcare providers and the general public.