TAKE A BACKUP.
Updating has messed things up for me on my RAID setup. Post update my windows partition has gone walkabouts, system recovery partition works, but it can't find the main windows partition.
After some playing around (ran the update program again) it broke further, one of the drives was no longer a RAID member, and it's serial number changed (before at the end of the serial number on both drives there were some odd characters, which have now gone on the drive that no longer reports as being part of the array)
I then played around a bit more with trying one drive at a time and both drives have got rid of the weird characters at the end of their serial number, and both are reporting as being non-raid members in the Intel RAID BIOS.
I'm going to see if I can recover anything using a Linux Live CD. Was foolish not taking a backup (I even thought about it too, but couldn't be bothered at the time because I'd never had a firmware update issue in the past) but there was nothing I really cared about on there apart from some recent save games.