Gemini Lake is still based on the 14nm Goldmont Plus architecture. You get the same cache configuration and the same Intel UHD Graphics, but with higher frequencies.
The Pentium J5040 is the new flagship for the entry-level market. This chip has a 2.0GHz frequency and an up to 3.2GHz Boost. That's quite a big increase versus the 1.5GHz base clock and 2.8GHz Boost of the J5005.
The first motherboards (with soldered CPUs) and Mini-PCs with the new Gemini Lake Refresh are expected in early 2020.