Well both are good CPUs. The Intel i5 3570k is usually the best option when it comes to gaming. The FX 8350 has it's benefits, but overall I believe the i5 3570k is the better option.
Things to consider:
* If you go with the i5 3570k buy a Z77 based mobo, so you can have all of the OC'ing options that you might want later.
* If you go with the AMD FX 8350, I would consider the 990FX based mobo if you can afford it. It might possibly have better upgrade options down the road.
in terms of better which it is, can u tell us how better fps and how much % and also what the extra percentage equates too and if it is noticeable? also can the human eye spot the difference or are we relying on benchmarks here? which in my opinion should be turned into time! (1 sec, 2 secs etc etc) if its secs or 1-5 fps i really dont see how ppl justify intel being much more better. real word scenario.