There is so much great talent across this country! Chicago, L.A., New York, Philadelphia, Atlanta, Charlotte (and other parts of NC), And now Houston is really coming up on the scene (as well as other parts of TX), and many other places..
However that being said, I believe NO OTHER CITY or metro area has the rich concentration of musical talent and gospel legacy that DETROIT has!! Detroit gospel artists include:
The Clark Sisters (Twinkie, Dorinda, Karen, and Jacky)
The Winans family
Deitrick and Damita Haddon
Vanessa Bell Armstrong
J Moss
Kiki Sheard
Evelyn Turrentine-Agee
Fred Hammond
Commissioned
Witness
Lexi
Ramiyah
Vickie Winans
Rizen (from Saginaw, MI)
Marvin Sapp (from Grand Rapids, MI)
and many others!! (I'm just naming them off the top of my head)

And that's not even to mention the rich history that Detroit has. The late great innovators in gospel such as Thomas Whitfield and James Moore, and the queen herself, Dr. Mattie Moss Clark. Also Bill Moss (Dr. Clark's brother), Donald Vails and the Choraleers, Tessie Hill, and many others.
The Gospel Music Workshop of America (GMWA) was born in Detroit, the Gospel Music hall of fame, and the community there in general is VERY supportive of gospel.
Some other currently popular gospel artists learned the ropes while they lived in Detroit, including Donnie McClurkin, and Byron Cage! And many other gospel artists have traveled to Detroit to record albums, work with Detroit producers, and hold release parties.
This is just the tip of the iceberg. There is just so much that goes on in Detroit musically. This just goes to show you that Detroit, hands down is and always will be the GOSPEL MUSIC CAPITAL OF THE WORLD!!!
Loopy