Pros
This is a very large Fortune 100 company that prides themselves on culture and how they treat their associates & customers. There are a lot of genuinely good people that work here that want to help you succeed. The pay is about average, but considering the benefits (including a pension) it's not that bad. At the end of the day, your path is up to you. There are so many opportunities to move around departments and/or the country. Just be advised that you will find more opportunities in Columbus, OH or Des Moines, IA where the corporate offices are located. If you're good at networking and not afraid to ask questions, there are really no limits on what you can achieve. Plenty of people are willing to mentor. With that being said, it's up to you and you alone to define what you want and then go and get it.
Cons
If you're not in Columbus, opportunities and resources can be extremely limited. A bad performance review can diminish your opportunities for advancement. You oftentimes get notes from management that seem to be focused on perception rather than results or efficiency. Be mindful of politics, but that's to be expected at a corporation of this size. Also, the archaic IT systems can prevent one from being competitive in the modern workforce. I believe the IT infrastructure is so large and complex that it's too difficult and expensive to keep up with the times. I have used software from the 1980s that really shouldn't exist anymore. The medical plan is one of the worst plans I've ever seen. You pay a high premium AND high deductible. They tried to justify it by referencing the changes in healthcare legislation. Nationwide's medical plan is not good at all compared to other companies who offer generous employer sponsored medical plans.