Topaz recently released the brand new Photo Ai 3.0 (click here). Now it has also completely revamped its website so that you can get a better overview of all the features. Take a look at the presentation pages: Photo Ai, Video AI, GigaPixel AI.
One more related news: PetaPixel tested all most known upscalers and claims GigaPixel AI is the best:
Overall, I was most impressed with Gigapixel AI. The results for the low-resolution file are especially excellent, far surpassing my expectations. It produces excellent levels of detail with minimal (or no) additional artifacts, even when going beyond 2x. I also enjoyed the UI of Gigapixel AI more than the other programs. It was clean, modern, and simple to use with an ideal way of seeing the preview of the upscaled images.