Pity the poor reviewers. Ideally, you'd like to have one product in for review at a time. Test it for a while, write up a review, and then post it at launch day. Then get the next product to review, which doesn't launch until sometime later. AMD pretty much nixed that approach with today's launch of not one, not two, but three desktop product lines all on the same day. Sites that just run some canned benchmarks and post the results have got reviews up, but some of the sites that do higher quality reviews with more in-depth analysis aren't done with everything yet.
Let's start with the one that wasn't even rumored: desktop Picasso. That is, the desktop version of the laptop chips that launched several months ago. This is just a refresh of Raven Ridge. Basically, take the Ryzen 3 2200G and Ryzen 5 2400G and add a few hundred MHz. That gives you the Ryzen 3 3200G and Ryzen 5 3400G, now available for sale on New Egg. There is technically more to it than that, as it's Zen+ cores on a GF 12 nm process node, but that's the gist of it. That's not the most exciting news, so good luck finding a review of it with everything else launching today.
Next is third generation Ryzen, in the desktop parts without an integrated GPU. This is a move to a Zen 2 architecture and a TSMC 7 nm process node, both of which are big news. AMD has caught or perhaps even slightly beat Sky Lake (and hence Sky Lake Refresh Refresh Refresh) in IPC. In other words, if you take an AMD CPU and an Intel CPU and cripple them to disable all but one core and run them at the same clock speed, the AMD CPU will commonly beat the Intel one outright.
The problem is that AMD hasn't caught Intel on clock speeds. The Ryzen 9 3900X that launched today has a max turbo of 4.6 GHz, while the Core i9-9900K will turbo up to 5.0 GHz. That tends to make the latter a little faster in single-threaded performance. Still, even if you compare it to the Ryzen 7 3700X that AMD distributed for review samples so that they're both 8 core, 16 thread CPUs, AMD tends to win at multi-threaded benchmarks and often by a lot. And while using less power, too.
One reason for this is that it takes the Core i9-9900K a whole lot of power to run that one core at 5.0 GHz. If you want to push all of the cores, it has to clock them much lower. A Ryzen 7 3700X isn't going to run all of its cores at 4.4 GHz at once, either, but it can come a whole lot closer to it than the Core i9-9900K. If you're commonly doing stuff that pushes a lot of CPU cores, Intel's mainstream consumer CPU line is now pointless. The upcoming launch of third generation Threadripper will probably make Intel's Sky Lake-X line completely pointless no matter what you're doing.
But what about gaming? Here, if you make things severely CPU bound, the top end Intel CPUs do beat the new AMD CPUs substantially more often than not. AMD does manage to win outright at some games, though. Even when Intel still wins, it's a whole lot closer than it was with the previous generation AMD CPUs. Furthermore, making the game CPU bound often pushes frame rates well into the hundreds. If you're heavily into e-sports and running a 240 Hz monitor, then yes, you still want a Core i9-9900K.
The problem is that Intel's clock speed advantage at the top end doesn't benefit you unless you actually grab that top end processor. The Core i9-9900K and Core i7-9700K both cost over $400 right now. If you need a CPU for under $370, Intel doesn't offer anything with a max turbo above 4.7 GHz. Under $230, make that 4.1 GHz. And then Intel's clock speed advantage disappears. (Prices are based on New Egg right now.) Intel's single-threaded advantage at the $500 price point doesn't translate to a comparable advantage at the $100 or $200 or $300 price points that most CPU buyers are more interested in.
The are some important architectural differences between third generation Ryzen and Sky Lake Refresh Refresh Refresh that I'd like to highlight. Performance of L1 and L2 caches look similar, though AMD has a larger L2 cache per core. It's when you go to L3 cache or memory that they're very different. Intel has a single, unified 16 MB L3 cache on the Core i9-9900K. AMD has two separate 16 MB L3 caches on their new die, one for each of the 4-core core complexes. For the Ryzen 9 3900X, it's four such L3 caches. For single-threaded performance, that doesn't matter, but if you're using both core complexes, that means that AMD has far more L3 cache bandwidth available than Intel. If the core complexes are doing completely independent things (so that it won't tend to be the same data cached in both L3 caches), that also effectively means it can cache far more in L3 cache. That plays a huge role in AMD tending to win at highly threaded benchmarks.
There's also a big difference between the memory controllers. Intel mostly sells large, monolithic chips. That means that when you miss L3 cache and have to go to DDR4 memory, it has to move data around within a chip to get from the CPU core to the memory controller, but the memory controller is on the same chip. Third generation Ryzen doesn't do that. The I/O die is a physically separate die from the CPU core die, so it has to hop to a different chip to get to the memory controller. That hop is over some sort of interposer inside of the socket, so it can offer a lot of bandwidth and not add that much latency. But it does add latency.
As compared to second generation Ryzen, Sky Lake and its many refreshes already had lower memory latency. As compared to third generation Ryzen, that advantage widens. Still, it's only adding another 10 ms or so, not the 70 ms that first and second generation Threadripper added when you had to connect to a memory controller based on a different die. We knew that hopping to a different die was going to add latency, and it was only a question of how much. I'd regard this as a relatively favorable result for AMD. But it means that Intel does have a substantial advantage over AMD in memory latency.
AMD tried to counter this by being able to have far more memory reads in flight than Intel. That will benefit AMD considerably in highly threaded workloads, but not so much in single-threaded ones. If you make a simple benchmark where you read a random memory address, and that tells you where to go for the next read, then read the next memory address, and so forth, then Intel will win, and by a lot. Or at least, that will happen if you make it over a large enough table to rarely hit any on-die caches. But if you do 50 of those at once, then AMD will win, as even if the latency for each read is higher, they can have a lot more in flight at once, so every nanosecond of waiting has the clock ticking for perhaps twice as many memory reads in flight.