It should be quite safe, but the motherboard manufacturor cannot guarantee anything because the RAM speed is above the nominal speed. The CPU is factory set to 1066 or 1333 Mhz.
But by overclocking or using Intel XMP you can easily overclock the built-in RAM controller. But this is never without risk. Your hardware probably won't instantly break but for the longevity of the hardware it can be a problem. An the other hand, if the CPU or motherboard don't support the memory it probably won't boot up so nothing will break.
I've built some Pc's using either 1600 or higher RAM speeds using Core i7 and X58 motherboards and I've never had any problems. If the RAM has XMP then the motherboard usually recognizes the memory and sets the clock speeds accordingly.