My five cities:
1. Salt Lake City MSA: Business, Captial, Tourism (Temple Square, Park City)
2. Provo/Orem MSA: 70,000 College Students, Provo is a great start-up business city, even if half of them are MLM's.
3. Ogden MSA: Trains & Transportation, Hill Air Force Base, Ski Resorts
4. St George MSA: Tourism, National Parks, Growth
5. Logan MSA: Utah State University, Agriculture
5a. Vernal: Oil.
more than 5, but I felt that it was important to add the Uintah Basin's oil to the list, though I don't think it's achieved top 5 status yet. If it continues to grow, the state should focus more on connecting that region to Salt Lake... Imagine the downtown growth of SLC should some oil companies want some office space