To the OP,
I had the same plan as you. I have a BS that wasn't making me any money, but still had a couple of years left to apply to med school. I thought that a 16 month ADN program would give me great medical experience (even though I have plenty), and support me while I work to get in to med school. I am currently in the first semester of the nursing program.
Perks: You get an understanding of actual pathophysiology, - in class and during clinicals - that you really may not get as a biology/chem/lib arts major. You will memorize the heck out of common medications. You will probably get as close to medicine as a non-medical school/mid level student can get. You can get a job that has wonderful benefits and great pay. Also, you can get practice at a good chunk of the residency scut work that you will probably have to do.
Cons: Not only is nursing school intense, but you spend countless hours learning how to look at disease and medical treatments as a nurse. For a premed student, this was a big shift in my opinion. Secondly, although you learn about the disease process, you still don't cover it as in depth as a medical student. Sometimes you glance over it just fast enough to understand why certain nursing interventions are carried out. Finally, there is so much work (care plans, preparing for clinicals, rotating through clinicals), that it's torture to do if a person really doesn't want to be there. Imagine taking a class that you hate. Now, multiply that class by four, and add an extra 20 hours in clinical and prep time for the class. If you aren't crazy about nursing school, it's difficult to deal with. By the time you put up with all the nursing theory and culture, graduate, pass the NCLEX, get a job (which takes 6 months to a year to feel comfortable with, without the extra stress of studying for premed classes), and get a bachelor's, you may easily be so burned out that you don't want to do ANY more school!
Don't forget, nurses wipe a$$, and collect all kinds of nasty specimens on a daily basis. They deal with irate family members, and spend hours connecting with really sick people. I don't mind it, but there is no way that I would make it through this process if I weren't crazy about nursing school (and I am).
Basically, don't do it. It takes too much time, money, and emotional energy if it isn't something that you really want to do. Accelerated programs are even worse for people who don't want to be there. Also, you may be asked why nursing school wasn't for you. I'd be wary. Just my two cents.
CrazyPremed