If you're unfamiliar with Nvidia's GeForce MX lineup of GPUs, it's the "at least it's not integrated graphics" product for ultrabooks. While the MX350 hasn't even been out for very long, Nvidia announced the MX450 today, and it should begin shipping in laptops this October.
The GeForce MX450 does have some notable improvements over its predecessor though, the main one being that it's built on the company's new Turing architecture, whereas the MX3xx series was still based on Pascal. The new graphics card also offers GDDR6 memory, although there's an option for GDDR5.
As far as where you'll actually see the MX450 show up, it's likely that we'll see it in ultrabooks that have Intel's upcoming 11th-generation 'Tiger Lake' processors. For one thing, the new GPU supports PCIe 4.0, something that no Intel chip supports right now, and no mobile chip supports either. Also, this is expected to start arriving in laptops this October, around the time that Tiger Lake starts shipping.
Intel is promising some solid integrated graphics improvements with its Xe architecture. Presumably, the MX series will continue to provide a modest boost in graphics power over what Intel has to offer.