The GTX 1660 Ti features a TU116 GPU with 1536 CUDA cores, a 192-bit memory bus and 6GB GDDR6 memory. There will also be a non-Ti version with 1280 CUDA cores that model is expected in early March, unless it also got delayed.
As a bonus, VideoCardz also has a photo of the GIGABYTE GeForce GTX 1660 Ti OC. This will be one of Gigabyte's cheaper cards for the launch, it's a model with a dual-fan cooler.