d[o_0]b points out that the recent v2.40 update might be responsible for some consoles getting toasted. The update has been pulled and the official firmware update FAQ page
has been updated with the following:
We are aware of a limited number of consumers experiencing an issue with installing firmware 2.40 on PLAYSTATION 3. While our consumer services department has seen a low volume of calls on this topic, we are committed to enabling the community and XMB access features delivered in the 2.40 update. In order to further assess the issue, we have temporarily taken the firmware offline for further testing. We are working diligently to isolate the problem for those few consumers and to identify a solution before we put the firmware back up. The Knowledge Center will be updated with information as it becomes available; please check back here for further details.