Ok, my current system is 3 weeks old and has never went to sleep on its own. The display turns off just fine but it never goes to sleep.
If I Sleep it manually it stays asleep just fine. This is an annoyance and I'd love some help tracking down the cause.
Here's a start, or rather, not a start I suppose:
I thought that anything that was preventing Sleep would be listed there, but there's nothing and it still won't sleep.