So the two surfaces: the bottom one is mostly flat, the front slightly higher, and the back surface is at a 20 degree angle or so off the horizontal. It's perfect for sleeping, watching TV, lounging around, everything ....
I'm not even sure if this is a real position or if it just got stuck here or accident. But I like it. I don't think I'll ever adjust it. I'd be too sad to have it go.
Update: Another cool property of perfect mode: the back side is higher, so it blocks the sun from my eyes in the morning and I can snooze for 60 minutes instead of 45. (I discovered that this morning...) Hooray!