Intel for sure.
MC makes good use of additional cores, but it does not scale to "truly massive" multithreaded performance to the degree necessary for an AMD core (which has, comparatively miniscule, Instructions Per Clock performance). AMD's Bulldozer cores are just not that good, and aren't a good choice for almost any "desktop" PC. They could be more competitive in small-form-factor devices (tablets, small-form-factor devices, and other places where the Atom and Ultra-Low Voltage versions of the Intel CPUs compete), but they don't have very many good design wins (other than, of course, the huge ones in the PS4 and XBone).
In other words, it still holds that for the vast majority of users, on a desktop: IPC is king.
Now, that doesn't mean you want a single-core machine. Balance is everything in life, of course.
I don't have specific recommendations on the CPU. I will say that you'd certainly be fine with a Core i5-class chip (the primary difference between the two being Hyperthreading) if you are planning to use a discreet GPU. If you aren't planning to use a discreet GPU, then the decision becomes murkier.