No, FX-series processors still aren't out. AMD has however pulled a neat little PR stunt by gathering a handful of overclockers—Sami Mäkinen, Brian Mclachlan, Pete Hardman, and Aaron Schradin—and letting them loose on an eight-core FX-8150 CPU. The overclockers purportedly pushed the chip to a whopping 8.429GHz, breaking a Guinness world record in the process. (AMD claims that, before the event, the world's highest recorded CPU speed was 8.308GHz.)
The chipmaker has posted a video of the action on YouTube, and it's something to behold:
Partway through the process, the overclockers switched from liquid nitrogen to liquid helium in order to reach lower temperatures. Wikipedia tells me liquid helium boils at just 4.2 kelvin, or 4.2°C above absolute zero, compared to 77°K for liquid nitrogen.
Now, from what I can tell, this feat didn't involve stability testing. The overclockers merely reached the record-breaking speed and recorded the result in CPU-Z. (Incidentally, the Hwbot database listing mentions a 3.2GHz base clock speed the FX-8150.) However, AMD notes on its official blog that speeds "well above 5GHz" were achieved "using only air or sub-$100 water cooling solutions." That ought to provide some encouragement to overclockers with more limited means.
Too bad the rest of us will have to keep biding our time until FX-series chips hit stores. AMD says the new processor line won't be out until some time next quarter.