The 2nd gen Ryzen chips are not based on the Zen 2 design, "Pinnacle Ridge" is basically a die shrink to the improved 12nm process from GlobalFoundries. Presumably, these chips will be launched as the Ryzen 2000 series, and will have better power efficiency and higher performance. Word is also going around that the second generation Ryzen processors may have support for higher DDR4 frequencies.
The new processors are also said to support higher DDR4 memory frequencies, at least thats what some folks have been whispering into our ears. This is likely due to the performance and power improvements that 12LP brings to the table. Low power and mobile variants of Pinnacle Ridge processors are expected to debut around April and 2nd generation Ryzen Pro parts are set to come out in May.