By coincidence, I'm taking apart a 40GB SKU this weekend to clean out the heat sink and replace the TIM with AS5. Hoping that will fix the hardware error otherwise it looks like bro in law will be getting a new PS3 Slim. Don't think he'll want to be without MW2 for much more than the weekend, so the race is on.
I'm pretty much expecting to see a ton of dust/pet hair/etc. inside since the entertainment center doesn't seem to get dusted ever. The first time I did a fan cleaning cycle, a cloud of dust literally flew out the back.
I think the reality is, a lot of people simply aren't going to do any sort of preventive maintenance on PCs and certainly not consoles, particularly those who don't treat them like objects of affection like a lot of users on this site.
On the plus side, since there's no intention to have it refurbed/repaired through SCE, it doesn't matter whether the fix works or not; it's just an opportunity to pull a PS3 apart.