I had four Wintermelon watermelons and took the seeds out to zap and save on Monday or so. I ate three of them; the other one was going bad. The seeds are black and smaller than most hlack-seeded winter watermelon seeds. The taste was good, and the texture was excellent. I have a feeling that both the taste and smell of larger fruits would be better. I know the smell can be, anyway.
Here's a picture of the first one I ate: