Intel's transition to building processors on a 10nm manufacturing process has been delayed repeatedly. Once upon a time, the company said that it'd go into mass production at the end of 2015; with its most recent financial results, the company pushed that back, again, to 2019. But Intel has also said that, although the yields aren't good enough for large-scale production, it has been shipping 10nm processors, codenamed Cannon Lake, to an unspecified customer.
That customer is Lenovo: the IdeaPad 330 has been listed by Chinese retailers, and it includes a mysterious processor, the Core i3-8121U. The name tells us the market positioning (it's an i3, so it's low-end), the power envelope (the "U" at the end means that it's a 15W chip), and the branding (the number starts with an 8, so it's going to be another "8th-generation" chip, just like the Kaby Lake-R, Kaby Lake-G, and Coffee Lake processors). This means that "8th generation" is a rather vague label that describes several different processor variants, built on several different manufacturing processes (two 14nm variants and now 10nm).
We didn't know much more about the chip until Intel published it on its Ark site. The Ark listing confirms that it is indeed a 15W Cannon Lake chip built on a 10nm process. It has two cores, four threads, a base clock speed of 2.2GHz with turbo boost of 3.2GHz, and 4MB of level 3 cache.
What else do we learn? The Cannon Lake part supports two new kinds of memory: LPDDR4 and LPDDR4X, both low-power variants of DDR4. This should enable reduced power consumption even with high memory system configurations, compared to the previous generation which only supported LPDDR3 in addition to standard DDR4. The maximum theoretical memory bandwidth figure has also been upgraded to 41.6GB/s, up from 34.1GB/s.
The Ark listing also says that the Cannon Lake processor supports more PCIe lanes, up to 16 from 12 (though the actual supported lane configurations appear to match Kaby Lake chips, so it's not immediately clear if this is correct). More peculiarly, however, the listing doesn't include any specs for a GPU. Virtually every mobile and desktop processor Intel makes includes an integrated GPU, and one would expect Cannon Lake chips to follow suit. According to this listing, however, the i3-8121U doesn't. The Lenovo laptop in question is specified as including a discrete AMD R5 GPU, offering no guidance as to whether the chip does indeed have a GPU.
As such, while Cannon Lake and Intel's 10nm manufacturing remain a little mysterious (the broader question of "why this particular chip for this particular customer?" feels particularly germane), we do now know a little more than we did before.