- According to AltPlusF4.com (linked above), PS3 Firmware 2.70 is causing bricked systems. However, they are not bricked, just 'locked up' primarily due to certain brands of PS2 to PS3 USB adapters being plugged into the system.
So for now, simply do not use these adapters on the new firmware.
To quote: The PS3's 2.70 firmware is causing some havoc out there with reports of bricked systems. They're not bricked, do not reformat.
If you have certain brands of PS2 to PS3 USB adapters plugged into the system on boot you'll get a blank screen, no sound and won't be able to connect your controller (adapter controller AND PS3 wireless controllers).
If you get the firmware update installed fine and then plug in your adapter, you'll lock the system up and have to do a hard reset. The only solution to this issue right now is simple - unplug the adapter and don't use it for now.
We know of two adapters currently (there are likely more) that are causing faux-bricks: TAC and Sumoto.
This is affecting quite a few people that use older controllers/instruments for game such as Guitar Hero and Rock Band so you can bet they'll make enough noise for Sony to hear them. With any luck, it will be a simple fix that they can get out fast to users.