never had a freeze on any of the two systems in my possession, they are the first generation of ps3/360 though.
preventative measures?
right!
rip em apart, both of em, and redo all the thermal grease regardless of how new the console is.
what i did, and i've razzed the bollocks off them both.
still gets a bit warm, nothing like OEM in any case.
naturally, the longer this goes by without address, the greater chances of console death.
i guess they don't make them like they used to eh?! (and as for my 360, backburner. the games selection and media usage makes me ill thinking about it.)