The newly remodeled Xbox 360, announced at E3 this week, will never show the three red lights of death.
That doesn't mean the system won't ever break, of course. So far though, many people who got theirs from E3 have enjoyed it and had it on for hours at a time saying it hasn't once shown any problems. What the No More Three Red Lights mean is that Microsoft's redesign has done away with that messaging system to let the user know that their console had bought the farm. In an interview with Phil Spencer, Corporate Vice President for Microsoft Game Studios, it was revealed to IGN (www.ign.com) that the new design has a different way to communicate any potential hardware failures.
Now obviously, the box has a way to communicate to you if something has happened...but yes, three red lights are not part of our sequence of telling somebody something is wrong. Obviously if you look at the success rate of the original 360s, we're very proud of both the way the company stepped up to support the customers that we had as well as the success rate we have with the box today. I think we've learned a lot. That learning has gone into the development of this [new] box. - Phil Spencer's quote on 360 Slim to IGN
Hopefully Microsoft learned their lessons with the old 360's so that the new Slims won't have any problems. Keep those fingers crossed!