If you have a Motorola Atrix 4G that is rooted and has an unlocked bootloader, updating the device via an OTA update will brick it. This being said you can recover from it by flashing the updated SBF via RSD Lite. Those of you that have bricked your Motorola Atrix this is how to recover after updating the device.
Currently the updated version of the Motorola Atrix 4G is software version 4.5.141 and as such the instructions will be for this update specifically. Future updates should be able to be fixed as well with the same method with the SBF for that version.
Fix Bricked Motorola Atrix after an OTA Update:
Make sure your Atrix is fully charged before beginning
Remove your SIM and SD Card from the device and turn it on
Press “…” button beside the Filename input and select the SBF
When asked to Extract or cancel, select extract
Plug your Atrix in via USB and wait for RSD Lite to detect it
Press “Start” and wait for RSD Lite to say 100% complete
Congrats you are unbricked and on 4.5.141 running Gingerbread 2.3.6
We aren’t responsible for the use of these instructions although they should fix your issue rather well. Also this is kind of a fix all for any other issues you have with your Atrix although it will completely wipe the device. Let us know if you have any questions or need any help.