Someone Somewhere :
The 3770K is an i7. Also, the 4960X is stupidly priced. Don't know where you got the idea they're for multimedia PCs.
It depends on what Xeon you're talking about.
Yes, the Xeon series is primarly made for workstations, servers and are often used in proffesional multimedia pc's that does heavy 3D animation and video editing + rendering.
Gaming pc's have no need for cpu's that are 6-core + 12 threaded or 8-core + 16 threaded for that matter. As the coding game producers are using most games will only use 1 core anyway, this however is going to change in the near future, where most games are going to start to benefit from multiple cores (hopefully we'll see this take effect in a years time).
I'll agree on the fact that the 4960x is slightly overpriced, and is far from a value optimized product. But if you have the budget for it (or not budget to follow at all), then grabbing one is not somthing you'd regret.