Yes, keyboard just above the knees. It's similar to the angle you'd get if you were slouching and your forearms were resting on the desk. Generally quite comfortable.

I think raising my hands up higher (90 degrees as you say) would actually be a lot worse. Never understood that aspect of all the more "real" laying desks.

I should note that I purposely don't use a mouse with this setup, because it would end up being quite far away and would need to be on a solid surface.