I was thinking that too. I started this when I first got my PS3, but never got very far because it's in my room and would keep me awake at night. More recently I would definitely worry about whether it would contribute to bringing a premature end to my system. Possibly not though, as most issues people have seem to be blu-ray related and I've hardly played blu-ray games at all on my machine.

Is it possible to set it to come on at a certain time and do this?