The problem is quite common at the PS3 forums. Every week, I see at least 3-4 threads over a PS3 console no longer reading discs (but then again, it's the biggest PS3 fan site and has tons of members). Most of them are 60GB consoles, since many of them have an older blu-ray disc diode (I believe manufacturing of 60GB consoles ended in March 2007). I've heard it happen to some 40GB/80GB consoles, but very rarely (Have only heard a few 20GB consoles not work, but there aren't many out there). I thought I heard of Sony extending warranties who had disc reading problems for some (this was back in January though). Be sure you still have your receipt.
One person who had a PS3 from another region and wouldn't be able to send it away, so he took an ear tip and some rubbing alcohol, cleaned the laser, and the games worked again. Two issues I'm hearing are PS3 consoles getting too dusty inside (causing disc reading problems due to the laser not being strong enough or something), or the laser gets stuck and needs to be adjusted.
Not being able to read disc is the most common PS3 issues, followed by only making three beeps, yellow light of death (hardware failure), and every once in a while a HDD problem.
So you can get a Wii that has no good games, an XBox 360 that has a 30% failure rate or a PS3 that has more errors than...than...I dont know but man that sucks. You should put a dead fish in the coffin...
All next gen consoles have problems. There were issues with some Wii consoles getting an error (mine has) and early consoles with Wii Connect 24. It's true there are many different errors with PS3, but the failure rate still seems to be no higher than 5% thankfully (from what I gather).
But I will say, the easy way to kill a PS3 is by Folding@Home too much. The majority of people I know who had PS3 problems (mostly with no longer turning on or HDD failure) have come from Folding too much (to a point the console got too much wear and tear).