There are 2 temps for AMD's. The core temp, which in your case is the package temp. The MAX for that is ~62. You hit 61 under prime. The second temp is the socket temp. Since these chips use a lot of power, 95-125w and 140w+ when ocing, the VRM's get hot and the chip itself drawing that much power gets hot, so the actual socket gets hot. Its MAX is ~72, which you 72 under prime.
Under real world, you will never see those MAX temps. Primes pushes a PC way beyond what it normally does, and it really works AMD's harder than needed for some reason. A lot of people use AIDA or Intel Burnin test for AMD's instead, but prime is the standard, so everyone just goes by it.
I say you are fine if that is after an hour. Again, no game or regular program will push it that far. Try gaming or maxxing it using a program you actually use and see what temps are. they are probably well within that limit.
For an example, I oc'd last night to 4.8ghz on my 8320. Under prime/intel/whatever stress test, I was hitting core 65/socket 77. Too hot and at the limits. But that's not real world. I like to do 3D fractals, and the one program I uses can use all cores, threads, etc. So doing a 15min fractal render, 8 cores, all 100% maxed, I only hit like 57 for the core, 59 for the socket. Almost 20c less on the socket when doing a real world software, not a stress test.
So in my case, that's good enough for me. My PC will never be finding prime numbers or finding peak gflop performance, it will be doing 8 core 3D fractals at the most and when it's doing that, it's well within the thermal limits. Playing a game like BF3, my temps are under 40c.