a) I thought the rendered image looked unrealistic, and not like something I'd want to actually use/carry. It's like something out of a 1970's sci-fi movie (pre-Star Wars, when all futuristic things were white, shiny, and looked unrealistic). Or like a late 1980's "stealth fighter" project (like the saucer of the Enterprise from "Star Trek: The Next Generation"). Or like a surfboard. Just blah.

b) The current prototype looks about as blocky/rectangular as most of the other tablet designs I've seen. Like the HP.

c) Prototypes are also rarely the final look. They've already said (in the videos I linked) that it will get thinner -- it's currently 18mm, and they said they're going to get it down to 14mm, I think. I expect they'll round out the edges and corners, as well. But even if they don't, it's still a sexy looking design to me. Far better than the render.