Almost everyone commenting here falls into two camps: A) "NYC/SF is great" and B) "I've been to Des Moines, it's great." But nobody here really seems to be comparing the two. If I live in SF/NYC and I want to move to Des Moines, what are the upsides? What are the downsides? Sure, Des Moines is a nice place with fun stuff -- but so are a hundred other cities in the US. What makes Des Moines different or a good enough…
For me it is about the community. I like building things. Here, in addition to building my own startup, I am part of a group of people working to build a great ecosystem. It's exhilarating and inspiring to be surrounded by other people who are working together to make Iowa a great place to live. Being a part of shaping that nascent identity is a good feeling.
That's, of course, not the only reason to live in Des Moines. The reasons, priorities, and motivations are different for everyone. I've heard everything from people moving here to raise a family (low crime, great public schools) to cost of living (paired with the low unemployment the standard of living way more than averages out), to the hundreds of miles of public bike trails, to the growing music and arts communities, etc.
But really, it is hard to know whether Des Moines is the right place for you since I don't know you. It may not be, but I love it here.
It is also always interesting to read outside perspectives. David Byrne (of Talking Heads fame) recently wrote about Des Moines and I think it captured a lot of the small "quality of life" details that are hard to pin down without experiencing them from a fresh perspective. http://davidbyrne.com/des-moines